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reefburnaby
01-22-2002, 01:13 AM
Hi,

Okay...here we go again...domolite

1) Isn't this stuff used in lawns ? How could it be reef safe ?

Well, domolite was actually formed in the ocean...a long long time ago. It is basically, the precipitation of calcium carbonate and magnesium carbonate in the ocean. This is same calcium buildup we that we see on our pumps and glass. It actually happens in the ocean too... Over time, the ocean floors are build up with the carbonates and compacted in to limstone, calcite, domolite and etc. As the earth tectonic plates shift and move, some of the limestone deposits get pushed up to form mountains and coast lines. This is where we find dolomite is mine and sold as stuff for lawns. In fact, it is fairly safe and it would have the same contaiminants as playsand (i.e. metal shaving from crushers and such). In fact, how does caribsea ensure all of their sand has no metals....big magnets ? So, it is best to run a magnet through your domolite (or playsand or even Caribsea), so that it is relatively clean. Still think it is unsafe ? Send me a rebutal.

2) Domolite, that's calcium carbonate and magnesium carbonte...if the DSB has low pH (because of CO2 in DSB), then would the magnesium dissolve in to the water and cause problems ?

To a certain degree, magnesium will dissolve in a fairly low pH. But, it is fairly unlikely that pH would be low enough to do that. Although there is a oxygen depleted zone in the DSB for anerobic bacteria, the anerobic bacteria are usually consuming nitrates and they don't produce that much CO2. Unless you are generating a tremenous amount of CO2 (like a calcium reactor with 30 bpm) in a small space, the buffers will absorb the pH drop caused by CO2 (or carbonic acid). Since the pH drop will be very small, the amount of dissolution that can happen in is considered insoluble.

Do I like Caribsea or do I have something against them ?

Actually, I bought my first bag of sand for my tank from Caribsea. I used it on my 20 gal and it seemed to do well. Sadly...it is now inside my calcium reactor images/smiles/icon_smile.gif But, I think they are a great product, but this stuff is expensive. So, I went and explored alternative ways to build a DSB. Today, I use domolite.

Anything wrong with Calcite/Carbsea ?

The think the thing that confuses me is why is Caribsea sand not white ? By definition, calcium carbonate should be snow white. And yet, Caribsea is not. As Steve (Stircrazy), it is actually kind of yellowish white. My Caribsea is the same off white. Domolite is snow white...

So, I hope that answers some of your questions.

- Victor.

[ 21 January 2002: Message edited by: reefburnaby ]</p>

Jeff
01-22-2002, 01:18 AM
Do you get royalties on this stuff in the lower mainland or something? :> Local distributor to the Revy perhaps? :>

Jeff

StirCrazy
01-22-2002, 01:23 AM
Victor, I e-mailed Caribsea this evening inquiring about the chemical make up of there sand. when I get a answer I will post the results.
I don't forsee a problem with them releaseing the make up as it is a natural mined product not a lab created one, so there is no company secreat to hide.

Steve

*disclaimer* I did not do this as I thought there are hiding anything or trying to pull the wool over our eyes, simpily I did this as all this discussion has made me curious.

reefburnaby
01-22-2002, 01:26 AM
Hi,

Good question. Sadly, I don't get royalties from them. How does 1% of sales sound ?

I work as an computer chip design engineer...it doesn't have much to do with domolite.

- Victor.

[ 21 January 2002: Message edited by: reefburnaby ]</p>

DJ88
01-22-2002, 02:13 AM
I’ll start my reply off with this and refer to it through part of my post.

http://members.shaw.ca/montipora/pictures/sand1.jpg


Steve,

There is the assay of Caribsea Aragamax. Save ya the time.

Victor,

I understand how Dolomite is formed. My problem is with the mechanical operations involved. Caribsea states right on the package of their product that there is No metals or harmful Impurities Do you get that on the package of dolomite? Caribsea is putting their name on this statement and to me I will believe it. Read the label. If it is not clear enough to read I will link to the full size image or email it.

<blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quoteSo, it is best to run a magnet through your domolite (or playsand or even Caribsea), so that it is relatively clean. Still think it is unsafe ? Send me a rebutal..

I just ran a magnet through my Aragamax and pulled out nothing. Now if I had a bag of Southdown I would do that immediately. It is playsand, not aquarium grade sand or gravel. How would it look if tanks started crashing and it was due to impurities in the sand? Especially where they state right on the product there is none? They would lose a whole lot of business. They make a fortune off of this sand why risk it?

IMO there are no standards (as there is no need) when dolomite is mined(or there is ones set for lawn requirements only). It is going on your lawn. They aren’t figuring on it being put in a tank with live animals. So what if some oil or hydraulic fluid gets into it. Who cares if the driver takes a leak off the side of the front-end loader? Shards of metal? Who cares. It will corrode in time and move down into the lawn. That is all. Add some Iron into the lawn. It may need it. Maybe some copper who cares, who knows? images/smiles/icon_rolleyes.gif

I care. Why take the chance I say. You have even said it is risky. Why risk an animal’s life to some unknown variable. It’s a game of Russian roulette IMO. Probably you will be fine most of the time But what if you get that bag with a hunk of something in it that will kill off the whole tank? What will you say then to some kid who just started and has invested every cent he has in it? Sorry? I’d rather send that kid to something that is made for his or her tank. If down the road they feel confident enough to experiment and are willing to risk the lives of the animals in that tank so be it. I still won’t recommend it.

With the chemical makeup of the Dolomite I understand that there won’t be massive dissolving of the substrate. But when I see that the main part of dolomite is MgCO3 I get nervous. In seawater you only have small amounts of magnesium in solution. In time your sand bed will dissolve. It takes time, but there is enough of a pH drop to get that breakdown. I run my reactor at 7.0 now and it is dissolving at the same rate as it was well below. So you don’t need the low low pH to break the substrate down. I am seeing this change in depth of my sand bed. So to a small degree it is breaking down releasing the minerals into the water. With the dolomite being 60%MgCO3 what happens when you start introducing all that Mg into the tank?

Randy Holmes-Farley even stated you should probably keep an eye on your Mg levels and if they get to high do water changes. So to me I read that as the Mg can increase in your system. How do the corals react to this increase in Mg? I don’t know. Therein lies my concern. If I don’t know, I won’t do it. That is my point with the chemical make up of Dolomite and how it interacts in my system.

<blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote Sadly...it is now inside my calcium reactor

Wasn’t it Aragamax we were comparing here? images/smiles/icon_wink.gif j/k

<blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote The think the thing that confuses me is why is Caribsea sand not white ?

Aragamax is not completely CaCO3. See the pic I posted. I am betting that the additional makeup of the sand changes that color. Anyways when it is underwater in my tank it looks white to me. Which is just fine and dandy.

<blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote Are we being "tricked" in to thinking it is pure calcium carbonate ? What is that stuff anywhay ?

I don’t think we are being tricked. They have stated what is in it and made the guarantee of what is contained in the Aragamax right on the package.

In all honesty I am still not convinced that Dolomite is a safe substitute. Caribsea packages and guarantees that it’s product is Pure and Safe. There are so many different distributors of Dolomite that I doubt they all have the same standards as Caribsea for purity…

[ 21 January 2002: Message edited by: DJ88 ]</p>

StirCrazy
01-22-2002, 02:22 AM
Um Darren is that the right pic? images/smiles/icon_biggrin.gif images/smiles/icon_biggrin.gif

another question Darren whare did this 60% magnesium come from? this is the content of the dolomite

mighty white dolomite LTD. lime.
it has a guarenteed analysis of
Calcium 30% Magnesium 17%
Calcium Carbonate55% Magnesium Carbonate37%
Nutralizing value expressed as CaCO3 equivelent 96%

size wise it stated
100% passing 10 mesh
86% passing 20 mesh
69% passing 40 mesh
62% passing 60 mesh
46% passing 100 mesh

for a final score of 80

granted it is 37% Magnesium Carbonate but the majority of it is still Calcium Carbonate @ 55%

Steve

DJ88
01-22-2002, 02:39 AM
Steve,

Sorry if I got my numbers mixed up but I am sure somewhere a make up of one tpye of dol;omite avaiable was 60%. I'll look into it further. Still to me 37% is a lot higher than <1.5%.

Just me tho..

I wanted to add a few points in as well.

Ok Dolomite lime is used for lawns. We all know that. We know the chemical makeup of the dolomite. Another concern I have is what happens to it after it leaves the processing plant?

It is a lawn care product. So where is it stored? With lawn care products. ie. fertilizers, pesticides etc etc. It is stored next to or with all kinds of other chemicals and other items meant for lawn use only. Who is to say if along the way someone didn't accidentally spill a bit of some pesticide or other toxin on the package of dolomite? How do you make sure that this doesn't happen? Once again all it takes is someone getting the worng bag that this has happened and pow. dead tank. Diazanon and Copper sulfate are two chemicals I can think of that are stored in warehouses with Dolomite. I am sure if we were to ask Scott he can tell us about how this stuff is around more things than we can imagine.

Why take the risk? If you want to and are willing to take that chance go for it. I just won't sit and not state my concerns. Killing a tank of corals is not worth saving a few bucks on a substrate.

I don't want you guys to think I am against you or anything. Please don't I just have concerns over using something that is not made for or processed for our tanks going in them. I can go on with more concerns but think I have made my point.

DJ88
01-22-2002, 02:47 AM
Addendum to my last..

Steve.. I was looking for the place I thougth MgCO3 was 60% and came across a link you posted about Dolomite lime in Washington State.

It took me to the Washington Dept of agriculture. All over the page were links to pesticide and fertilizer management. The page was called Fertilizer Product Info.

I know it's chemical make up is not toxic. But those names make me nervous. Especially when it comes to my tank. I worry about getting anything close to my tank that may harm it in anyway. Heck I am careful with windex anywhere in my apartment. Putting something in that is concidered a fertilizer in the agrigulture industry freaks me out.

Silverfish
01-22-2002, 02:51 AM
Well.. if my tank full of SPS and a couple of clams (in the near future images/smiles/icon_wink.gif ) crashed because I cheaped out on the substrate, I would be pi$$ed off!!

No question what I use.. not worth the risk. images/smiles/icon_smile.gif

Like Darren said.. it is an expensive hobby, and the sand is just another part of it.

I have to say it is a bit tough putting out the $ on sugar sand that I did for my tank, and it is only a 55g!! but, on less thing to worry about!

StirCrazy
01-22-2002, 02:59 AM
heh, ya I see your point but dolomite is used forincreasing the ph of soil and that is it. but having said that yes there are lots of dolomites that had additives in them (ie. slow release agents, kalk type lime, ect.) that is why it is important you make sure what kinda dolomite you are looking at.

Darren, that picture you posted doesent show the make up of Caribsea it is the picture of how to use a power head to clear your sand bed faster images/smiles/icon_biggrin.gif but that was good also as I wanted to see that again images/smiles/icon_wink.gif

Steve

DJ88
01-22-2002, 03:03 AM
Huh? you sure.. I see a pic of the bag of aragamax.. hmm let me see something.. I think you needed to hit refresh as the image that was there was the drawing. I wrote over it. I bet you still have the old one in your cache. images/smiles/icon_smile.gif

Look now.(or in a few seconds.. )

And hit refresh on your browser. images/smiles/icon_biggrin.gif

[ 21 January 2002: Message edited by: DJ88 ]</p>

Dolf
01-22-2002, 05:02 AM
I really am interested in this topic. As I have stated I am considering the use of dolomite and because I know the composition and particle size of Mighty White composition (http://www-app2.wa.gov/agr/prodinfo.asp?pname=31010) through somebody else’s previous post I will be waiting till spring for Crappy Tire to import it. (I will not take chances with the others.) It is sealed in a plastic bag and I would not consider it to be a major problem. I have worked in warehouses where they handle both sealed food and chemical products (though not as nasty as pesticides) and if they consider that we are safe from it then I'm not going to fret over the fish.

Right now I am researching it and came across a post by Randy Holmes-Farley in another forum where he says "After all, where would the magnesium go? It's not being precipitated inside the plant (I presume), so it is likely being actively pumped out of the plant by another protein to maintain normal internal magnesium levels. A 100 gallon tank contains 492 grams of magnesium. To significantly deplete that, the plant would need a huge sink for all that magnesium."

To me this suggests that first, magnesium is not depleted very rapidly " Fortunately for reefkeepers, it is present in abundance in seawater and is depleted only slowly." (From the above link.)

And secondly it seems to me that 492 grams in a 100 Gal tank is a lot. (love how everybody combines metric and imperial measurements these days.) It would seem as though there should be some room for a bit more without affecting the organisms negatively. (I could be wrong as I am not a chemist nor a biologist.) It just seems that with regular water changes there is room for some of it to dissolve. It seems doubtful that a DSB would even dissolve 10 grams of magnesium each week because it would not be very long before you would have no sand bed.

In the same reply Randy suggests using a Hatch kit to test both the magnesium levels and calcium levels and it would be interesting to see the results in a tank with a dolomite bed.

As to the question of how polluted the dolomite may be, I have given it more thought. First, the pollution of the operator using the ground as a toilet should not be a huge problem as the nitrates etc would get taken away in the tank the same as fish waste. If I recall correctly there was even some suggestion that clams even need the nitrates and yes, you could use your tank as a toilet to provide it. (Bad and rotten as that may sound, it would keep others from reaching in your tank images/smiles/icon_biggrin.gif .)

The grease would be minimal and as I said there would be very little oil in the finished product when you consider that they would be using a loader with a 5 cubic yard bucket and even if there were a small leak it would provide less pollution to a fifty pound bag of dolomite than I do when I reach in the tank to clean the glass after working on cars. (Yes, I do wash, but there must be some residue.) If you were concerned with the hydraulic fluid you could skim the top of a bucket you poured it into first.

I do not care what they say, there would be a minimal amount of metal in the aragonite. They are not digging it out of the ground with a plastic machine and sand is VERY abrasive to the bucket of any machine. Also they screen the finished product so they can sell sugar fine etc... and they would run it over the same metal screens as the company producing dolomite would. The only difference that I can see is the metal off the crusher at the dolomite mine and even then it is a very small amount when you consider how much product is produced to wear a set of hammers down.

No matter what machine the company pulls the aragonite off the ground with I would bet it is well greased as pins and overhauls are expensive. I am not sure that they have not taken some steps to ensure that no grease gets into the product, but I have never seen a loader or excavator that would not pollute the end product with just a little.

One last chemistry related thread and comment on the dolomite. Here is a quote from aquarium frontiers where the author is talking about limestone versus crushed coral in a reactor. "The limestone was significantly lower than the crushed coral in a wide range of trace elements, including aluminum, boron, chromium, cobalt, copper, iron, phosphorus, silicon, sulfur, titanium and vanadium. Of particular concern to me were the lower concentrations of iron and phosphorus in the limestone compared to the crushed coral I’d been using." And "Comparing the limestone to the Super Calc Gold analysis performed by Bingman...shows the limestone significantly lower in aluminum, copper, iron, manganese, lead, mercury, nickel, silicon and zinc."

Anyhow, the link to the whole article above is right here. (http://www.animalnetwork.com/fish/library/articleview2.asp?Section=&RecordNo=1571)

I hope that provides some food for thought. I am not saying that dolomite should be used and I am having some second thoughts about it myself. However, from the info I was able to dig up it does not seem like it would cause a system crash and I found it interesting that it was lower in the heavy metals.

-Danny

On a side note not related to reefs but related to my sanity I keep having a pop-up widow appearing to me that comes up as a rotate…html. If anyone can tell me how to rid myself of this annoyance I would really appreciate it if you could e-mail me or send a PM. Thanks.

[ 22 January 2002: Message edited by: dan150 ]</p>

reefburnaby
01-22-2002, 05:15 AM
Hi,

Colour ?

CaCO3 = white
MgCO3 = white
Al2O3 = white (I should know, I lived near a Alumninum smelter for 17 years. This stuff is gross when it is all over you car. )
NaCl = white
SrO (this really doesn't exist like this) = SrCO3 = gray-white when expose to air.

I think we still need a better explaination.

Darren,

I wonder if there is a titanium or platnium excavators or backholes ? Then we would be sure that none of the metals used in processing would be harmful to our tank. Just kidding images/smiles/icon_smile.gif

You have to give it credit that Domolite has been use for a while.

Yes, domolite will dissolve at 7.0. Only thing is that the domolite has to be at a pH of 6.0 to dissolve at the same rate as calcite. So, it is going to dissolve very slowly. BTW, I worked out the numbers and calcium carbonate will start to siginifcantly dissolve at a pH of 7.4. For magnesium carbonate...6.4.

I guess time will tell who is right. Wish me luck !

- Victor.

[ 22 January 2002: Message edited by: reefburnaby ]

[ 22 January 2002: Message edited by: reefburnaby ]</p>

DJ88
01-22-2002, 03:46 PM
Hey Victor,


<blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote Colour ?

Ok that is the colors of the individual compounds, what about in the ratios found in carib sea? How do they interact when the bond to form the aragonite? I am no chemist but I assume that once you molecularly bond a few different compounds they will interact and some properties will change(ie color). And I have no prob with the color of dolomite of caribsea. Once it is in my tank(caribsea) it looks nice and white. That is the least of my concerns. But it seems to bother you.. images/smiles/icon_wink.gif hee hee

<blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quoteYou have to give it credit that Domolite has been use for a while

Until you had brought it up I hadn't heard of it. I have concidered using silica but not dolomite. To me it is a lawn care product used to raise the pH of the soil. Yes it is white but that is where my thoughts ended.

<blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quoteI guess time will tell who is right

It's not a matter of right or wrong to me. It's is it safe for general use? As I look at it right now it is a game of russian roulette. You may be doing ok but what about the person who has jsut started and loses everything due to chemical contamination of their tank? If it is a fully stocked tank that was switched over and all livestock was lost what do we say then?

StirCrazy
01-22-2002, 07:23 PM
It was once again pointed out to me that Caribsea products (ie. sugarsand and argamax) are mined in a quary in the same fashion as southdown and dolomite. so having said this, it stands to reason that there is the same chance of getting contamanation in each of them.

In a different Post I have discovered that Dolomite was one of the substrates of choice for people years ago when the only other stuff you could get was crushed coarl and oystershells, I guess not eveyone had read that or they just skimmed throught it and forgot. images/smiles/icon_biggrin.gif

After a lot more reading last night I decided I will use dolomite and not caribsea in my tank, if some people want to consider this experamental you can, or just unsafe...go ahead, but from about 2 months of researching this, I found that dolomite was widely used befor caribsea came about and there are people still running it on tanks that are 2+ years old with no problems. but like the disclamer reads **make sure you get the right kinda dolomite, one that has not been altered to provide a slow release or any other properties.***

so now the question remains.. why are somany people using the caribsea sand, well because it is new? (we all know how this hobby thrives on NEW) is it beter? ( I don't know about that yet)
Because it is made by an aquarium supply company?
(Bingo, if a aquarium hobby company is making it people will automaticly assume it is better. after all IceCap is the most effecient, and cost effective ballast money can buy.... right? images/smiles/icon_biggrin.gif )
sorry I coulden't resist images/smiles/icon_biggrin.gif

why are they using dolomite? well it is Cheep (1/10th of the price) It is white (beautifuly white) it is better than caribsea? ( I don't think so but I will hazard to guess that is is just as good.) it has already been provin to be better than crushed coarl or crushed oyster shells in that it has less contaminants in it.

Now I am not saying run out and buy it or don't buy the other stuff I am just saying keepa open mind and don't condem somthing on the basis that it wasen't specificaly sold for fishtanks, or that it is cheeper there for it must not be as good. cuz we all know this doesen't hold water.

Victor, I have one request of you if that is ok, can you find Mg test kit somewhare and test your tank? maby if some one has one when they come over to your house on the weekend they could bring it with them if you don't have one. I would be curious to see what the level is befor and after a water change.

one more thing I feel needs to be pointed out again, in my test between sugarsand and dolomite, the sugarsand added MORE desolved particals to the water colume than the dolomite did. this was also not just a 1 time test I had 8 wine glasses going for 4 seperat tests (much to the wife's dissaproval images/smiles/icon_smile.gif )and they were all consistant.

Steve

[ 22 January 2002: Message edited by: StirCrazy ]</p>

Troy F
01-22-2002, 09:48 PM
...after all IceCap is the most effecient, and cost effective ballast money can buy.... right?

I still think so. Of course you have to figure in the cost of bulbs and energy consumption. (sorry couldn't resist images/smiles/icon_wink.gif )

Darren, don't slap me for being off topic.

reefburnaby
01-23-2002, 01:38 AM
Hi,

Colour ?

Well, my only fear is that it may contain a form of oxide like rust. If domolite is 58/38 calcium carbonate/magnesium carbonate and it is fairly white. Why does 95-98% calcium carbonate looks so...ivory. I don't know...I thought you would know images/smiles/icon_smile.gif I guess it points out that as pure as arganite is, there is still some foreign compounds in there.

What's the difference between lawn and a coral ? Well, really they are both sensitive to chemicals and petro products. They both need fertilizer (i.e. trace elements). If you have cyanide in the lime, they will kill both the coral and the lawn (and the trees). Domolite lime isn't some stuff that you arbitrarily get from a mining shaft, there are standards since they are also use to grow fruits and vegetables. So, there is a certain quality level...pretty close to fit for human consumption.

In the early 90s, keeping SPS was like playing russian roulette. Only thing was that you knew that there were five bullets in a gun that could carry six. That didn't stop people from trying...at $75-$100 a pop. Today, we have beautiful tanks that have only SPS. Without those pioneers...we would avoid SPS like flowerpots. Without trying, I'll never know if I could succeed.

But, I will get my test kit at J&L tomorrow. Hopefully, it is in stock. I will keep you posted.

- Victor.

DJ88
01-23-2002, 02:39 AM
<blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote cyanide in the lime
Cyanide?

I am more concerned with pollutants and other chemicals this dolomite may come in contact with not just at the processing level but at the shipping and storage level.

Dolomite is stored with fertilizers and insecticides. Those prodtucs won't kill your lawn as easily as they will kill your tank. Am I wrong to think that?

Yes caribsea products are costly, I give them that. But they are giving you a written gurantee on each package of No impurities. When a company tells me something in print I will take it as truth. If it isn't I have grounds to go after that company for false advertising.

I think it is great that you are trying out ideas. But when someone new who is just starting in the hobby comes online and asks for help I am leery of sending them off buying something that isn't meant for your tank but should work fine. You yourself even said it is risky. And I have read all kinds of posts specifying on other boards that there are several different kinds of dolomite. And only to use one in particular. I don't want someone new to the hobby to glance over a post see the word dolomite and go rushing out fill their tank up and wipe it out because they bought the wrong stuff.

Maybe I am off base with this but I will NOT put anything in my tank(water) that is not produced or made for an aquarium. I am very passionate about that. If something happens due to a product made for my tank I can approach that company about the failure or impurties in that product. What is Revy going to do if you had fertilizer that seeped in the dolomite and it wiped out a tank of livestock? Laugh? or look at you like you had three heads? I won't put the animals in my care at risk. They are thriving now and I will keep it that way.

I understand you want to try it out. And I say go for it. When a company can say to me that there is no risk of impurities or other substances in the Dolomite and that it is safe and has been packaged and shipped for aquarium use I will then buy it and use it. Not till then. I am not one to risk a single coral or fish's life to a risky substrate.

As for the increse of Mg in your tank. I'd like to see the measurements over time. I do believe that with a proper 4" or greater DSB you will get a low enough pH to dissolve the substrate. I have seen it in my tank and if you look others have as well. This is due to a lower pH at the deepest areas. Will it put enough Mg in the water to cause problems? I dont know. It is only recently that DSB's have come into use. When Dolomite was in use before it was with plenums or on its own but not in the amounts we are putting in now. I searched to find others using it and so far came across you, Steve and possibly one other who are using it at teh moment. Others used it in the past when all that was available was crushed coral and oyster shells. But in that day it was all abotu a thin layer overtop of a UGF or plenum a bit later on. And of those only you are running a DSB(I am correct to assume it is a DSB?). So in effect you will be the first to see if there is an increase in Mg levels.

reefburnaby
01-23-2002, 04:53 AM
Hi,

I will pass on the cyanide part...it was just an example. As for pesticides, that's actually a controlled substance. So, it should not be any where near lime nor is it suppose to spill out. Domolite packaging is actually much better than one would think (like a concrete bag). If domolite gets wet or has a runoff, the concentrated domolite is quite corrosive to green plant life (due to high pH). So, the bags are design to protect that from happening. Besides, if there is going to be any crosscontamination (say fertilizer), then what...1% of your lime will be fertilizer at most ? Even 1% is pretty hard to acheive since it would have to leach past the paper and plastic protective covering of the bag. That bag would be in pretty bad condition at that point...I think you would pretty ignorant to buy that bag.

Come to think of it...there is a little secret that I use when buying lime. I only buy the bags that are not expose to the outside. Usually, these bags of lime are on a crate. A selected number of bags are always touching another bag and never expose to the elements. I pick those ones.

As for a newbee taking this as a defacto standard (Domolite that is). Well, if a newbee is reading this board and research about domolite, then he would be spending the time to see all sides of the story (i.e. if you do a search on RC...there is tons of info on this topic). As you know, bbs are full of different types of people. Some say the true, some don't know what they are talk about, some misread the question and etc. With so many opinions, the newbee isn't go to say...look "Victor" said it is alright....I am going to buy it right now. Victor is not a Dr Ron, Dr Mac, or even a Randy. Why should the newbee believe me in 100% confidence ? I am just one reefer out of many thousands giving my opinion. I believe this is what a board is for and I think a newbee already understands that.

As for magnesium slowly leaching in to the system. Did you know that magnesium slowly precipitates too - to form domolite or just magnite (pure magnesium carbonate) ? It is quite normal and that was one of the proponents for using domolite in the past. Today, salt mixes have higher than normal magnesium levels to compensate. So, regular water changes have been able to replenish magnesium levels. So, what will happen in my tank. The rate of preciptation is dependent on the levels of magnesium in the tank. Higher levels...higher precipitation. So, if the dissolution rate of increase is slow enough, the preciptation and dissolution should find an equilibrium where both are happy.

BUT...we will see. Time will tell. images/smiles/icon_biggrin.gif

- Victor.

[ 23 January 2002: Message edited by: reefburnaby ]

[ 23 January 2002: Message edited by: reefburnaby ]</p>

powerreef
01-23-2002, 09:41 PM
This is a great debate folks and it is nice to see how much research has been put into this subject. I have been keeping a SW aquariums for 19 years and am one of those that used to used Dolomite as a substraight. Now one thing to remember is in those days there was no choice and very little knowledge. Now with the knowledge available know and products I would choose not to use Dolomite. Thier are a number of reasons for this choice , but it boils down to not worth the risk. Thier have been many studies measuring the effect Magnesuim on aquaria, and it has been found that animals exposed to high mag concentrations in SW begin to show significant relaxation (ie: works as anaethesia) and prolonged expose causes mortallity in almost all species. In the oyster farming bussiness Magnesium concentrated SW is used as a shucking aid, as in it causes theoysters and clams to relax to the point to where even if you drenge them out of the water and drop them on the dock they are still wide open.

Another thing that scares me is the effect that Magnesium has on alk and cal. As i'm sure you know magnesium will slow the percipitation of cal.by attaching its ion to the carbonate ion of calcium carbonate. What effect would this have on calcium if it sat in a tank with such high levels of mag. carb.. Another thing to remember is in seawater, more than half of the carbonate ions present at any given point in time are ion-paired to magnesium, and this substantially reduces the free concentration of carbonate ions available to precipitate with calcium.

I geuss what i'm trying to say is that magnesuim at natural levels is good , but at high levels the fact that joins with other minerals and chemicals and produces biproducts is not good. it is also absorbed by most corals and rock in your tanks and can have problems thier to.

Put all that crap together and it say I'll spent the extra 200 on the right stuff. now i dont know if i have made any sence in my ramblings but take it for what its worth.

Mike

StirCrazy
01-23-2002, 10:44 PM
<blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr>Originally posted by powerreef:
I have been keeping a SW aquariums for 19 years and am one of those that used to used Dolomite as a substraight.<hr></blockquote>

How long was your tank running on Dolomite?

<blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr>Originally posted by powerreef:
Thier have been many studies measuring the effect Magnesuim on aquaria, and it has been found that animals exposed to high mag concentrations in SW begin to show significant relaxation (ie: works as anaethesia) and prolonged expose causes mortallity in almost all species..<hr></blockquote>

Can you post some of the links to thease studies please, I haven't been able to find anything on this yet and I would liek to read it.

<blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr>Originally posted by powerreef:
Another thing that scares me is the effect that Magnesium has on alk and cal. As i'm sure you know magnesium will slow the percipitation of cal.by attaching its ion to the carbonate ion of calcium carbonate. What effect would this have on calcium if it sat in a tank with such high levels of mag<hr></blockquote>

you would be able to obtain higher calcium levels.

<blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr>Originally posted by powerreef:
Another thing to remember is in seawater, more than half of the carbonate ions present at any given point in time are ion-paired to magnesium, and this substantially reduces the free concentration of carbonate ions available to precipitate with calcium.<hr></blockquote>

this is TRUE, and it is a good thing. if the Mg didn't pair with the carbonate ions the calcium would.. and if calcium did pair it would drop out of solution and create more sand. exactly what you don't want . now because the magnesium is causing more calcium to stay in solution that means there is more calcium available for your coarls and other creatures (that require calcium) this is one of the benifits of adding magnesium to your system, it allows you to have HIGHER Ca levels. I would hazard to guess that anyone with over 450ppm ca has a higher magnesium level than natural sea water.

<blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr>Originally posted by powerreef:
I geuss what i'm trying to say is that magnesuim at natural levels is good , but at high levels the fact that joins with other minerals and chemicals and produces biproducts is not good.<hr></blockquote>

ok you confused me on this one and I wasn't sure what to say but Magnesium is fairly non reactive and dosent combine with other metals. to back this up I will use a quote from a chemmist who is a reefer.

"Interestingly, the average residence time for a magnesium ion in seawater is tens of millions of years, substantially longer than calcium (a few million years) and aluminum (100 years), but less than sodium (about 250 million years). In a sense, this is an indication of how reactive magnesium is: it stays in seawater a long time because it's fairly unreactive, but it does get taken out of solution more readily than does sodium." by Randy Holmes-Farley

now what I think you might have been talking about is what he referd to as "Poisoning of Growing CaCO3 Surfaces". in fact the magnesium doesen't combine with the calcium but the magnesium carbonate forms a coating around the calcium carbonate and when it is large enuf it precipatates out of solution. remember if something falls out of solution it is no longer a concern as it can't interact. this is one of the ways the level of magnesium in a solution is controled.

I have to say this post made me do a lot more searching and I had to reread a lot of stuff to be sure on what my instints were. now having said all that I am interested in reading thease studies on the higher magnesium levels you were talking about.

Steve

powerreef
01-23-2002, 11:52 PM
Hey steve I not tring to say that the use af a Dolomite bed will cause all life as you know it in your tank to die, I'm just saying is that thier are a lot of untested results of such a substraight, and if we concider the larger ammount of money we pay for corals, gadjets and so on why cheap out here. I'll try to answer some of your questions.
<blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr>How long was your tank running on Dolomite?
<hr></blockquote>
my tank was up and running for about 3 years using this stlye and o combination using dolomite. This said we did not any real corals to talk of back then it was basically white sand coral skelitons and the nastest sea cr\itter we could get.

<blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quoteCan you post some of the links to thease studies please, I haven't been able to find anything on this yet and I would liek to read it.

I will have to search them out , but i will get them to you tommorrow.heres one
http://www.animalnetwork.com/fish/library/articleview2.asp?Section=&RecordNo=2856

ihad discussed the effect mag has on cal in the tank, and you made a general statement that it was good, and indeed it is but at normal levels, what would it be if the mag was increased to to 10 times its natural level.magnesium has a big impact on the rate of precipitation of calcium carbonate. so would that concintration all most reduce calcium precipition to nil or just slightly, would this give us calcium super saturated SW, would this be ok? I dont know do u.

I stated mag ions attach through pairing with other minerals. oopps i meant other ions from other elements.

thier were a couple of things i had stated that you had not retorted on, as in the adverse effects on aquaria inhabitants, that should be something for you to concider. Here is a section out of an article by Craig Bingman, a pretty well known author on aquaria . it reads as follows

Dangers of excessively high or low magnesium

Some aquarists are apparently adding magnesium supplements to their aquariums without performing any testing for magnesium levels. This is a potentially dangerous practice. I can point to no evidence that higher than natural seawater magnesium concentration has a beneficial effect on marine organisms. However, there is evidence that higher than natural seawater concentrations of magnesium can harm marine organisms.
Magnesium salts have been used as a “chemical shucking aid” on oysters and other shellfish for many years (Whyte and Carswell 1983). Magnesium chloride is also used as a relaxant or anaesthetic in pearl oyster culture (Norton et al. 1996). Namba et al. (1995) report persistent relaxation of the adductor muscles of the oyster, Crassostrea gigas, when exposed to solutions of magnesium chloride. The degree of relaxation was dose and time dependent. Higher concentrations of magnesium chloride and longer periods of exposure increased the number of individuals showing persistent relaxation. Significant relaxation was observed in groups of animals exposed to concentrations of magnesium only six times higher than seawater for periods as brief as 30 minutes.

Culloty and Mulcahy (1990) indicate that magnesium salts make an inexpensive anaesthetic agent for Ostrea edulis. In studies of anaesthetic agents for the scallop, Pecten fumatus, Heasman et al. (1995) found that magnesium chloride at 0.31 molar was a good anaesthetic. However, magnesium sulfate at the same dose caused excessive post-anaethesia mortality, a finding that may be interesting and relevant to individuals who use magnesium sulfate heptahydrate (Epsom salts) as a magnesium additive.


anyway it just doesnt seem worth it buddy

DJ88
01-24-2002, 01:16 AM
We meet again Victor.. images/smiles/icon_biggrin.gif

<blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quotethere is a little secret that I use when buying lime

Isn't that something you should share with others to minimize the chances of getting a bad that may be contaminated? Hmm???? Where was this tidbit when you were suggesting dolomite? Keeping the safer bags for yourself were you?

<blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quoteif you do a search on RC...there is tons of info on this topic

I did before you posted this. Here is a rough breakdown of what I found.

[list] 9 were for adding a tiny amount of dolomite to a Ca reactor to increase Mg levels. 6 Using as a substrate yourself, Yellow tang & hatton3(asking about cycling with dolomite 3 posts) 3 of Steve asking about dolomite 4 Used with UGF in the past 2 Used as kalk substitute 2 Beginner mistakes 2Grain size (linked to reefs org) Looking for Southdown. Recommended dolomite by person above to reefs.org. Taking dolomite out Dr Ron recommending to get rid of UGF and Dolomite as substrate. Troy talking to Randy Holmes-Farley where he recommends keeping an eye on Mg levels Using Dolomite with UGF and wanting to switch. Scooter asking if it was good to Dr Ron Store selling old bags of. Worst purchases. Talking about progression of substrates trough the progression of the hobby. listed as a substrate used with UGF's Silica sand use. Was in the thread. Flame Angel bought the wrong dolomite Keeping Mg levels up. Looking for cheap substrate Dolomite sandbed doesn’t buffer as well as aragonite or oyster shells. Lower pH. Tests done over two months in Salt Water. Super calc gold looking like Spelling mistake.

That is a summary of Dolomite on RC. Three people using it. Of which I think you are the only one using it in a DSB. So the only one who will see what will happen to the MgCO3 in a DSB. I did see lots of uses in a Ca reactor to INCREASE Mg levels in the system. Once again I wonder what will happen as the Ph in your DBS drops and the Mg starts to enter into your water column. You according to your tank description only do in-frequent water changes. And that worries me. Randy Holmes-Farley said that you should keep and eye on your Mg levels and I hope you do. I know some will precipitate out but I bet you can get your concentration of Mg up beyond levels safe in your system. It is a hunch I am gathering from the responses and articles I am seeing on the boards.

To me other than you and two others using dolomite(one was a 12 gallon FO), it isn't in use very much. I searched on reefs.org and found two posts. Both by the same author. In the past when there wasn't the abundance of substrates(Aragonite based) as there is now it was used solely with an UGF. Not in a DSB so those can be an example of it's use but not when used in a DSB. That is a while different creature.


<blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quoteWhy should the newbee believe me in 100% confidence

To a newbie in this hobby you are very knowledgeable. You have a tank up and running. They don't know for how long or how short. All they see is you making a recommendation for Dolomite as a substrate. And that you are using it. It took quite a few posts to get your secret out of you about getting bags in the middle of the stack.. lol. images/smiles/icon_wink.gif When someone sees the possibility of saving a few dollars in this hobby their eyes get cloudy as to all the things involved. I have done it. I'll admit it. As someone new all they will have to see is someone who has many posts recommending something and they will do it. Hey these people will go and buy a skimmer that is good for a 40 gallon tank and throw it on something over 100 gallons if they see someone saying they do it on a board. Heck I bought a SeaClone for a 90 gallon tank!!!! I thought it was enough. images/smiles/icon_eek.gif images/smiles/icon_rolleyes.gif

<blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quoteToday, salt mixes have higher than normal magnesium levels to compensate

According to this study(link below) done not all are so. Most are lower. I use Instant Ocean and it is almost identical. Mg levels in synthetic sea salt and Natural Sea Water. (http://www.animalnetwork.com/fish2/aqfm/1999/mar/features/1/photo2.asp)

So what happens if the Mg levels are increased even higher? That is my point. I use Iocean and it keeps my levels at or near NSW. To me your levels will increase over time. A noted chemist in this hobby has said as such. What do you say in regards to that?

<blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr>So, if the dissolution rate of increase is slow enough, the preciptation and dissolution should find an equilibrium where both are happy.
<hr></blockquote>

You are sure about this? Once again, Randy Holmes Farley has said that you should keep an eye on these levels. If there was no reason to worry about it increasing why would he mention it? But that is me interpreting a chemist and what he is saying.

I guess in time we will see. Hopefully it isn’t for the worse.

StirCrazy
01-24-2002, 01:21 AM
powerreef, all is good, I am debating this as I want to find out more. how long ago was this you were using it? and didn't you have mushrooms or softies or such?

that article is the one I quoted from by Randy Holmes-Farley, I have probably read that about 20 times now hehe


I totaly agree about the epsom salts. aka magnesium chloride. if you check you will find that this is used as magnesium seams to have a great bonding ability with chlorine and as a chloride you have a wonderfull anaesthetic but as free magnesium or as magnesium carbonate you would not get the same results. remember that the second part of the equasion
sence 0.0453 moles per kilogram = 1100 parts per million, you would have to have a Mg level of
7525ppm in a "salt" form just to be a good anaesthetic.

Steve

StirCrazy
01-24-2002, 01:38 AM
hey here is a link for Darren images/smiles/icon_smile.gif
http://www.aquariastore.com/aquaria/servlet/estorepck.hes1203?1,34607706

and this is from Aqualink on setting up a plenium

"Bob Goemans wrote that this area will have a pH of 7.6 or so, and that dolomite is the preferred substance. Dolomite is less calcerous than crushed coral, and therefore will not dissolve as much at this lowered pH."


Steve

StirCrazy
01-24-2002, 01:54 AM
<blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr>Originally posted by DJ88:
You are sure about this? Once again, Randy Holmes Farley has said that you should keep an eye on these levels. If there was no reason to worry about it increasing why would he mention it? But that is me interpreting a chemist and what he is saying.

<hr></blockquote>

ok Darren just a couple things images/smiles/icon_smile.gif if you are going to use parts of that article put the whole paragraph in as what you quoted is very very misleading. what the whole post said is

"Dolomite, as you know, contians both calcium and magnesium carbonate. I don't really see a big problem with it, but maybe a little one. It's possible that as it slowly dissolves, the magnesium level may rise, and you might want to take a measurement of the magnesium once in a while to make sure it isn't rising too high.

I'd expect that routine water changes would keep it in check, and a big one would certainly correct it if for some reason the sand were dissolving fairly fast."

also one more thing if you check into all thoes posts on RC (I have) 90% of them are talking about dolomite gravel (large stuff). now weather this makes a difference or not.. I don't know.

Steve

DJ88
01-24-2002, 01:56 AM
As a bit to add:

I was reading through Fishnets library and came across this from the Advanced Aquarist forum;

<blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quoteThe level of magnesium will determine if your solution will form aragonite or calcite. Corals and shellfish generally only form aragonite. If you are looking for maximum biological calcification you must not have excess magnesium.

As well Andrew brought this to my attention;

<blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote Mg++ allows Ca++ to go up but if it goes up beyond a reasonable ratio it will cause alkalinity to drop -- you know the whole Ca++ Alk balance thing.

I looked it up and found reference to it on Fishnet during a discussion with Randy Holmes Farley about dosing Epson Salts to boost low Mg++ levels:

<blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr>

Bob –Given that Magnesium bonds tends to form on the xtals(crystals) of Calcium carbonate
thus inhibiting their dissolution, is it not possible that the reduction of
the total #s of CO3= in solution might decrease the pH?

Randy Holmes-Farley - Whether it did that on it own as MgCO3 precipitation (or something else like
Mg(OH)2), or on the surface of CaCO3, that is how I believe the pH would drop.
Of course, in the test I ran there was no solid surface of CaCO3, but in a
tank there would be.

Buffering effect would not be changed for any period as the SO4= would stand
in until the CO2 infusion would re balance.>>

I don't agree with that. The buffering (alkalinity) will be depleted. This
would be true whether you believe that hydroxide or carbonate or both were
removed from the system. Even after reequilibration with CO2, the solution is
permanently decreased in alkalinity, and will reequilibrate at a lower pH.

<hr></blockquote>

Just something else to consider.

Canadian
01-24-2002, 02:00 AM
Do you know who Bob Goemans is? He's the "guru" of plenums. He argues that DSB don't work (or at least not as well as his mighty plenum). I hardly think that anything that Bob Goemans has to say regarding the efficacy of substrates pertains to a discussion about it's use as a substrate in a DSB. In addition, Bob Goemans completely discredits himself because his information is so slanted by his bias and desire to reap the rewards of payment from companies who supply him with products to "review" which, oddly enough, always seem to receive favorable reviews.

The art of quoting ideas is that you use quotes or paraphrase the ideas of people who are well respected peers within the particular area of expertise. Bob Goemans doesn't really fit any of these criteria. Sure he writes for a magazine, and sure he's written a couple of books, but I've got a book shelf full of text books with outdated or inaccurate information -- having your work published in publications which lack sufficient peer review can be done by any monkey with a type writer.

DJ88
01-24-2002, 02:18 AM
Steve,

Never heard of the stuff. But if you can get me more info I'll read about it. How is it's coating "breathable"?

In my readings about Dolomite on RC I found an interesting test done with Dolomite as a substrate and it's buffering ability. These are the results of a test done on three different substrates. It is done in salt water over a two month period. I found these results on RC. I do wish it had oolitic sand in its comaprison as well. But to me it illustrates that Dolomite isn't as good a buffer as has been made out.

<blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quoteLaboratory experiments comparing the buffering capacity of crushed oyster shell (composed primarily of the most soluble forms of calcium carbonate -- high magnesium calcite and aragonite), crushed coral gravel, and dolomite sediments compared to that of silica sand. Of course silica sand had no buffering capacity and the tank pH dropped below 7.0 within 90 days. The other sediments didn't work so well, either -- after two months in a tank with a reasonable bioload, the pH of seawater in the tank with dolomite was 7.4-7.5, the crushed coral/aragonite was a little better at 7.7-7.8, and the oyster shell was the best at 7.8-7.9 -- again though, this was over only 2 months. In any case, none of them buffered the pH enough to rely on the capacity of the sediments alone to provide buffering over the long-term.

One more thing to concider. That fact coupled with the use of a Ca reactor, which tends to depress the Ph of a tank, may be of some concern.

<blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote also one more thing if you check into all thoes posts on RC (I have) 90% of them are talking about dolomite gravel (large stuff). now weather this makes a difference or not.. I don't know.

If that is the case then there is less info on dolomite on the boards than I thought. If 90% are on gravel and not the small grain, then it is even more difficult to get the correct info is it not? More for a newbie to sift through and decode. How many people understand all the nuances of a DSB when they are brand new to this hobby? or what the current sciences are behind all the technical information available? not many. All the more reason to proceed with caution with regards to Dolomite as a substrate for someone new to the hobby.

Victor,
I say go on with your tank, all the power to you. images/smiles/icon_biggrin.gif But I am still hesitant to say go for it to someone new.

[ 23 January 2002: Message edited by: DJ88 ]</p>

DJ88
01-24-2002, 02:38 AM
Mg++ and problems with calcification of corals.

<blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr>By Ron Shimek:


Additional calcification reduction may be due to the substitution of strontium for calcium in the enzymatic pathways necessary for calcification. Strontium(and other doubly charged positive ions such as magnesium, barium and zinc) will occasionally substitute for calcium in the chemical processes that a coral uses for skeletogenesis. The substitution of strontium(Mg/Ba/Zn) for calcium by corals, mollusks, and fishes appears accidental (Sadovy and Severin, 1992). However, strontium(Mg/Ba/Zn) is not a twin of calcium and reacts somewhat differently than calcium, and may significantly slow down the calcification process. Thus, if the conditions are otherwise good for the corals, the addition of Strontium(Mg/Ba/Zn) would inhibit calcification.
<hr></blockquote>

[ 23 January 2002: Message edited by: DJ88 ]</p>

Dolf
01-24-2002, 09:48 PM
When I posted a reply on reefs.org and said they may wish to give dolomite a try it came with the warning that it is second hand knowledge. I do plan on adding a DSB in spring when I can get it (provided that the tank is still up- if I move North to a camp job I do not think they will let me take my reef on the little plane images/smiles/icon_biggrin.gif ) Right now after the lighing upgrade and new pump I cannot afford the aragonite to put in the tank so one way or the other it will be spring before the main tank gets the DSB. (I need to wait for the dolomite to be in stock or for my "real" job to afford it.)

As for the magnesium I guess we will see. I asked Dr.Ron a question about the PH in the lower levels of the DSB and so far no response. I will provide the link at the end and will post his reply when received. This should help to either stir up debate about the Magnesium not being as soluble as we think or more soluble depending on what the answer is and who will wish to disagree.

From what I know (thanks to a response from a reefer who seems very knowledgeable on another board) it would take a PH of roughly 7.6 and a large amount of CO2 to pose a problem. I think that there is a lower number if it is not in the presence of CO2 but I will have to search. If the response from Dr.Ron comes back that the PH is 7.6 or lower then I may start questioning the use of dolomite. Above 7.6 and I would assume that there will be fewer arguments? (Or not)

here is the link (http://www.reefcentral.com/vbulletin/showthread.php?s=&threadid=58766) and I only hope the good Dr. has an answer and that the research has been done.

-Danny

[ 24 January 2002: Message edited by: dan150 ]</p>

DJ88
01-24-2002, 10:15 PM
Nice to see you here Dan..

Glad you are joining in. The more the merrier. images/smiles/icon_smile.gif

I'll keep an eye out for Dr Ron's response.

By far this is one of the most enjoyable debates I have had in a while.

You agree Victor? images/smiles/icon_biggrin.gif

StirCrazy
01-25-2002, 01:38 AM
ok I am not sure about this so I am asking about it. with the lower regeon of a DSB there have been studies that have showen that it is lower PH than the water colum, now from the last 23 years of keeping planted fresh water tanks and trying out tones of different soiles ranging from kittly litter to laterdite, I have always had a4 to 6" bed in my freshwater tanks and although I think we get some of the same benifits in nitrate reduction as I get anerobic zones in my fresh tanks and no matter how much nitrate I add with my fertalizer I cannot get my nitrates in the tank above 0 ( I want it to stable out at 10ppm)
Now that I have explained the madness behind my thinking I am wondering if what is going on under the sand bed affects the water colume at all? why do I think this? well in freshwater tanks we add iron and phosfate ritch fretalizer sticks below the sand bed for root feeders. they desolve and feed the plants but I never have a high iron level or any phosfates in my water colume. now in a reef tank whare the PH is 8ish lets say the bottom of the sand bed is 7, in theory stuff that will desolve at 7.2 shold start desolving how fast do you have to replenish your sand bed? seeing that arganite desolves faster than dolomite it would take a lot longer for the same volume in dolomite to be desolved, which would in turn result in a slower rate of particles being released into the bottom area of the sand bed.
my theory is that as the elements are working there way throught the sand bed to towards the water colum, most will bond with other particles in the substrate and never make it to the water colum. in a sence the upper 3 to 4 " of the sandbed is acting like a filter causing most of the elements to precipatateout of solution befor it can reach the water colume. does this make sence? think about it,

if this wasn't happening you would never have to add kalk, run a calcium reactor or use stuff like ionic B. all you would have to do is keep replenishing your sand bed because at a ph of 7.5 I have showen that arganite will desolve untill it buffers to 7.8 ish in my exparament.

well I have more to say but I am going toleave this at that. this post doesent say which is better just gives some food for thought on what is actualy going on in a DSB. like I stated I have been running DSB and quasi DSB, for about 23 years now and this is something I have been thinking about for a long time, just with freshwater and not salt, but the mechanics are the same.

Please I want to hear your thought on this as it is just my theory and if you have evidence to prove it wrong then I stand to learn from it.

Steve

reefburnaby
01-25-2002, 02:12 AM
Hi,

Yes, I agree that this is one of the most interesting debates we have had in a while. Thankfully, it was a mature debate...not a screaming match.

I don't think I want to pull out my domolite right now...just before the meeting images/smiles/icon_biggrin.gif I'll give it a year or two and see what happens.

- Victor.

powerreef
01-25-2002, 03:02 AM
hey boys are we having fun yet. Here is a couple of more tid bits for the debat.
This is an article from The Conscientious Reef Aquarist, it dealt with a number of sand bed issues but here is the one that dealt with types of substraigts

"Dolomites

(CaMg(CO3)2 are the least soluble source; they barely fizz when cold hydrochloric acid is test-dripped on them. Dolomite, as the poorest buffer, should only be selected for sparsely populated systems, and only for cost considerations. There has been speculation that it is possibly contaminated with toxic metals (Dewey 1984).

Calcites

(CaCO3, e.g. limestones, marbles are almost pure calcium carbonate; they are more soluble that the various sources/types of dolomites with their regular calcium and magnesium structure, but less soluble than...

Calcite with magnesium impurities.

Coral sand, crushed oyster and coral rock. These are the most suitable media and buffers.

Size (2-5mm), shape (spherical), grading (all the same), and circulation (2+ gsfm, the more the merrier) have been gone over under properties"


Hers another article from Aquarium Frontiers it talks about the needs for sand beds and types and also had this paragraph in it.

"One of the last but most overlooked advantages of a substrate is the ability for calcium and carbonate ions to be naturally released into the water by its dissolution. This natural process helps maintain high calcium and alkalinity levels, while reducing nitrates, phosphates, and iodates. Do not use Dolomite or Gypsum as they contain excess levels of magnesium and sulfate respectively. Dolomite may be used to help maintain magnesium levels in conjunction with a calcium reactor. Only use small amounts in conjunction with aragonite and closely monitor magnesium levels."


anyway thiers 2 more and I'm to tired to get more. you know this stuff is just gym chalk right

DJ88
01-25-2002, 03:03 AM
Steve,

I am getting a few things together to answer your questions.. Just so you know.

Victor,

I would NOT want to change a sand bed jsut before a meeting. I have change substrate out before.. ick ick ick ick hee hee.

See ya saturday.

Dolf
01-25-2002, 08:23 PM
The response to the PH question I asked has been answered by Randy Holmes-Farley where in part he said "In my tank, the sand bed has a pH in the mid to upper 7's. My sand is calcium carbonate (oolitic aragonite), which is dissolving at that the low end of that pH range. I'm quite sure that dolomite will also dissolve at that pH. But, the diffusion of magnesium up to the surface is going to be slow, and the magnesium level in seawater is more than 5 times the calcium (on a mole basis). Consequently, I don't see the dissolution of dolomite in deeper regions of the sand as being a big problem."

He also makes reference to a fellow named Spotte who did an extensive write-up in "captive seawater fishes." I would like to see if I can find this as it would probably answer a couple of questions that still remain.

For now I am still committed to adding Dolomite now more that ever just to study it and see the effects. If nothing else came out of this for myself I now know that I will be keeping a close eye on the magnesium levels and testing for it once a month. The link to the question and whole answer (well worth reading) is http://www.reefcentral.com/vbulletin/showthread.php?s=&threadid=58766

-Danny

Shadetree
02-26-2002, 09:38 PM
FYI, most of our dolomite comes from Washington where these results are from Check out LEAD, NICKEL, ARSENIC and some of the others.

PRODUCT: DOLOMITE

TOTAL METALS IN PRODUCT ppm

Arsenic <6.25
Cadmium <1.25
Cobalt <1.25
Mercury <0.1
Molybdenum <2.5
Nickel <1.25
Lead <6.25
Selenium <12.5
Zinc <3.75

And the other one,

PRODUCT: DOLOMITE

TOTAL METALS IN PRODUCT ppm

Arsenic <2.5
Cadmium 0.76
Cobalt 1.5
Mercury <0.0278
Molybdenum <1
Nickel 0.412
Lead 49
Selenium <2.5
Zinc 224

http://www.wa.gov/agr/

Scott

[ 26 February 2002: Message edited by: Shadetree ]</p>

StirCrazy
02-26-2002, 10:07 PM
I personaly have decided to go with sugar sand as I did a month long test on about one pound of each substrate and I wan't totaly happy with the amount the lime compacted. it might be harmless but it was a little to hard for my liking. having said that this is the sheet for mighty white dolomite.. I am not sure what brand you posted Shadetree, maby generic?

PRODUCT: MIGHTY WHITE DOLOMITE LIME

GUARANTEED ANALYSIS (%)
TOTAL METALS IN PRODUCT (ppm)

Arsenic <2.5
Cadmium 0.3
Cobalt 0.5
Mercury 0.005
Molybdenum <1
Nickel 4.9
Lead <2.1
Selenium <2.5
Zinc 5.1
The symbol "<" indicates the minimum detection limit. The metal was not found at or above the minimum detection limit.

Steve

Shadetree
02-26-2002, 11:51 PM
Most of the Dolomite purchased originates from or through Washington. It does not really matter who packages it because they all buy it from the same manufacturers. I currently have over 2200 pounds of it in the back of my truck for work.

Scott

Cazoom
04-29-2007, 09:10 PM
after going over all the posts does anyone ever use dolomite in their ca reactors or otherwise...
I was just given a 100 lb bag of dolomite (unused)
an older gentelman used as his sandbed mixed it with crushed corals in the 70's for his reef tank and had a few bags left in his garage he never used..
personally i wouldn't use as a sand bed.. but after all the reading i'd use a few cups in a filter sock to suppliment my tank once in a while to keep up my magnesium and calcium..( I have been doing this for a few months now)
wondering if anyone used in ca reactor as it seems to be a good media for that..