why are we running DSB and is it for the right reasons

[StirCrazy]

after reading several posts of late on DSB problems (including the 37 pager on RC) I have come to queston weather a DSB is a long term nitrate reducer, or is it infact a nutrent/polutant sponge that has a finite life and will cause problems down the road. If it is the later, then how do we deal with the potential demise of our present DSB's and how do we set up tanks in the future to safe guard against this?

I have thought about this for the new tank I want to do and this is what I am thinking.

1, make a base in the display tank of agracreat (or something) that you can "glue" sand to to simulate the look of a sand bed.

2, have a large remote sand bed set up but only using sugar sand about 1 to 2" deep so you can get the denitrifacation benifits out of it, but leave it cheep enuf to dispose of it every few years. (what kinda of square footage of sand bed are we talking about to be a good bacteria driven denitrifyer for a givin size of tank?)

I liked the idea of having two remote sandbeds with staggered start dates.
that way you could change one bed every year so you only go 2 years on a spicific bed.

so lets hear the Idea's/opinions that I know we have on this board :mrgreen: remember this is not intended to be a barebottom vs. dsb argument but rather a dessusion.

Steve

[Canadian Man]

Great Topic Steve!
Well my idea with my sand bed in my new tank is just 2 inches of sand. I have this same setup in my 90g currently. If I do need to change it in the future I guess I could syphion some of it out and add new sand but hopefully this is not nessecary.

I like the idea of a remote sandbed but you alway's hear that it's not as effective.

Would it not be as effective if you had a 230g display with no sand bed and you ran a 75g and a 100g with sandbed's plumbed into the main system?

Sand does look nice in a reef tank IMO though.

[Quinn]

Would be nice if someone conducted a true experiment on this. It could actually be done, you'd think RC could sponsor it or something. All this talk and no actual testing. I'd really like to know if I really needed to put 4" of sand in my tank, I would rather have done 2" or so.

[StirCrazy]

I will be the first to admidt that I went with a sandbed because everyone else was and all I could find to read about them was good.

I don;t understand how a remote sand bed could be not as good for nitrate reduction, if you get good flow throught it it will reduce. I to also think a bare bottom tank looks unfinnished, this is why I sugested making a bottom that looks like a sand bed.

the only regreat I would have is not haveing the feather dusters and such that grow out of the sand. but this could be acomplished by making holes in the bottom agracreat and filling them with sand :mrgreen:

the reason I want to get the sand out of the main tank is that if infact they are a proverbial "ticking time bomb" then you can change out the bed with out disrupting the main tank simpaly by isolating that tank for a couple weeks while you pull out the sand and let the new stuff settle.

also this would allow you to stir the bed up when you do water changes and syphen out the junk with out clouding your main tank.

Steve

[StirCrazy]

I'd really like to know if I really needed to put 4" of sand in my tank, I would rather have done 2" or so.

you can achieve denitrafication in as little as 1" of caribsea sugarsand, the 4" is the min recomended for the diversity of snad bed creatures.

Steve

[Aquattro]

Agreed. I had a 2 inch bed with no NO3 detectable. Dr. Ron "cohersed" me into adding sand to get 3 or 4 inches, as this was "better".....After 6 months with the deeper sand, I see no difference at all. To do it again, I would use 1-2 inches in the display tank and add it after the rock. That way portions could be removed down the road without tumbling any rock piles.

[Wilty]

I understand what your getting at but I don't understand how its a ticking time bomb. Is it the non-removal of trapped wastes that aren't getting eaten/broken down?

I'm a firm believer that a sand bed is needed in the main tank for reasons of feeding. Any food missed by the crabs/fish/corals get eaten by the brittle stars and other worms in the sand bed. Vacuuming the sand will kill all the life in the sand and I refuse to do it. I chose to use Cucumbers, Gobies and other sand sifters to move the sand around.

When I moved and had to pack up my tank, I lost a few fish when I accidently stirred my sand and spiked my nitrates. So I may need to rethink my own opinion lol

[Doug]

Guess I can put my 2-bits worth in, as I was part of the 40 pager. :smile:

I followed the trend also by going to deep sandbed. I dont know if they work long term or not, and wont argue that point. I can tell you none of mine did. They always had some sort of algae on them. When I moved twice, moving the sandbeds, they were the stinkiest crap I have smelled, worse than my skimmer gunk.

Now I am an experienced aquarists, I had tons of sand critters to "eat" whatever. I run top line filtration equipment. Never mattered. Most reef tanks I have seen in person, have cyno problems on their dsb.

They do remove nitrates, no doubt about that. I have always made sure when posting on removing my dsb, that I run a large turf scrubber, so nitrate removal is not a problem for me. That way someone does not copy me, just cause I did it. Its up to them.

I do have several inches of fine sand in the back, because of my wrasse. The front has rubble and/or Geo-Marine crushed coral. The animal used to clean it is called Doug Lowey & the python cleaner. :lol:

We are settin up a friends new 180 this weekend and his dsb from his 120 is going into the 100g rubbermaid sump. Its unlit this way and can be cleaned if necc. and still provides de-nitrification. His 180 bottom will have a fine layer of the same crushed coral.

[Fishster]

I have had my DSB's running for a couple of years now and I have been very happy with them. I have not seen any problem algea or any other problems with them. I am using them because I believe that they are closer to natural than a barebottom tank and they add to the biodiversity of the tank which is what I like about reef tanks. That having being said I have never cone through moving one which sounds like it could get ugly. Also it remains to be seen what happens after the 5 year mark if I see a dropoff in biodiversity this may be a factor. As it stands now I just don't see enough evidense to make me want to remove any sand.

[Wilty]

I was just thinking of just removing the waste/life from the sand in sections over time with a vacuum. Like a little every year so it doesn't get saturated. And not all at once to flux the system

[Troy F]

I too got caught up with the DSB despite being very apprehensive about the whole thing. I love the look, I like having the bio-diversity and more animals are available to you. I wavered back and forth for sometime even after I'd spent $400 on sand. I discussed the issue with Scott, Marc, Jamie, Darren and a few others and really it came down to 50/50 with no real solid evidence either way. There certainly have always been two camps on this issue, the problem has been that one of those camps became waaaay more vocal than the other and completely swayed the vast majority of reefers out there.

It'll be interesting to see the long term effects of DSB. One of things that really opened my eyes was Dr Shimek's latest claim that we have to replace all substrate periodically do to detritus/heavy metal pollution. It certainly lends credibility to the anti-DSB lobby. I've no interest in reading 37pages of Shimek disciples battling it out with Jerel and Galleon on ReefCentral (guessing at the combatants; I haven't opened the thread), I'll wait for evidence from those around me and my own observations. So far, I'd say they're more trouble than they're worth.

[Aquattro]

So far, I'd say they're more trouble than they're worth.

Troy, I think this to be true given the way we currently use them. I think shallow sand in the tank and a remote DSB is the way to go. With the remote bed, management becomes much easier. I think the potential plankton resulting from these beds is great, and if we could replace small amounts over time, toxic buildup could maybe be avoided.

[Troy F]

I agree 100% and wish I'd thought about it more carefully. Like you, not only did I add one (against my better judgement), I set the rock on top so that removing it would require a massive amount of work :redface: .

[Wilty]

Hey ummm thanks guys, I'm setting up a new tank and I think I'm convinced. I'm going to have shallow sand in the main and DSB in the sump/ref. Sorry that is now a bugger for you to make any changes . .. But I appreciate your experience :-)

[StirCrazy]

One of things that really opened my eyes was Dr Shimek's latest claim that we have to replace all substrate periodically do to detritus/heavy metal pollution. It certainly lends credibility to the anti-DSB lobby.

This is the problem Troy, the anti-DSB side is saying Dr. Shimek's high metal theory is bunk and not valid. Randy's (RHF) tests have shown the opposite of the good Dr.'s but what the major consciences seams to be that it is caused by high Organics. even Dr. Ron is starting to say that we cannot come close to replicating the ocean's bio diversity in out tanks as his original counts were 10X to low so instead of 100 organisms in a given area in reality it is over 1000 organisms in that area. Also he is now saying that instead of the 500 to 1000 types of "critters" that are commonly found in the reef mud of the ocean in home aquaria there are only 32 different types commonly accounted for.

Also there have been tests on the benefits of plankton produced by a DSB and if my memory serves it right it was Toone, that demonstrated that any plankton developed was either the wrong type or of an insignificant amount to feed our tanks. Also I have found that DSB's were originally used to create a stable high nutrient environment in labs and such to make the keeping of LPS and softies easier.

So now this brings us to another intersection in the road ahead, it looks like for a LPS/Softie tank a DSB is good, but for a SPS tank it isn't. This is not my conclusion but rather the general condenses that seams to be running around between all the people who are big in the hobby, I am merely trying to make head and tails of it.

So the conclusion I have come to is that we should look at a DSB in two ways the first being aesthetically and the second being a bacteria driven denitrification bed with a finite life.

Steve

[kari]

I like the idea of two remote sand beds, yet the deep part still bugs me. I have no proven theories to add yet some short term results. I have been using about 2cm sugar fine to bare bottom (star polyp covered glass) on half. The small fuge has about double the depth of sugar fine.

Denitratifation is working fine since water changes have been basically not done unless bagging outgoing stuff. Nitrate levels read 0 on my only test kit. Tank is fed 2xday.

The look of the sand bottom appeals to me but somehow I got a nice green front lawn :confused: No real algae problems yet.


---How about a remote dsb tank(s) with the bottom partitioned into say 4+ sections which could be siphoned out/cleaned and replaced at intervals. Smaller disruptions more frequent I guess. The older sections would reseed the serviced part quickly. Maybe I'll just make another drink and shut up. Is coke good for fish since I just poured it on the mysis instead of the rum?

[Buccaneer]

Kari ... I like the idea of the remote sandbeds ... I have about a 6" bed in the sump and about a 3 " in the refugium and anywhere from 3 " to 4 " in the display tank ... I saw your " lawn " in your tank and thought it looked pretty cool ... in hindsight I would probably have done a very shallow bed in the display or even none at all ... the GSP looks very cool and would allow me to do a all SPS tank with heavy circulation and not worry about sand blowing everywhere ... hmmmm :smile:

Cheers

[Aquattro]

Is coke good for fish since I just poured it on the mysis instead of the rum?

Actually, I'm told Julian Sprung has used coke to feed his goniopora. Rumor is that his new product may contain coke :razz:

[EmilyB]

I went with 1.5 and closer to 2 lbs per gallon of live rock when I first got into the hobby. I just saw some older pics of my tanks....and I never had nitrate or algae problems then.

I also jumped on the sand bandwagon.

Now I have a sandbed four years old that is just a shitload of crap. I purchased live sand every year for it, etc. I am in the process of replacing rock, and removing sand. I've never had the problem with an inch or so of sand in some smaller tanks. But none of those small sandbeds have been up four years either.

[Quinn]

...or is it a crapload of shit, Em? :razz:

I'd love to pull an inch or two of sand out my tank but it would probably spike my tank.

[sumpfinfishe]

When I was in Germany a few years back, I visited some serious fish stores there and asked about this subject. The 6 or 7 people that I spoke with, all had DSB's setup for 10 years or more. I was told in order to keep things clean, some would siphon out 25% once a year and replace it after a good cleaning, others told me that they would simply stir it up and run a canister filter for a few days, and the rest told me to go with an inch or two and to use lots of critters like snails and crabs.

My DSB is about 4 years old now, as I replaced my entire SB after two years into reefing-don't ask :mrgreen: I plan to keep my 2" DSB until I see reason to change. My only concern is that if we eliminate or reduce our DSB's aren't we not going to see these harmful elements transfer to our LR or worse to corals and fish :exclaim:

To make a final comment on this great thread, I am planning next year to clean 50% of my entire DSB. Sure this is going to be a major rip-out even in a 27gl, however I would rather spend an entire day cleaning my reef rather than loosing 6 years worth of hard work and beauty. :biggrin:
cheers, Rich

[StirCrazy]

To make a final comment on this great thread, I am planning next year to clean 50% of my entire DSB. Sure this is going to be a major rip-out even in a 27gl, however I would rather spend an entire day cleaning my reef rather than loosing 6 years worth of hard work and beauty. :biggrin:
cheers, Rich

See you are never letting your bed get old. by changing it you are getting rid of saturated sand and replacing it with new. what you are doing was originally described as a no no by Dr Ron as the original premise of the DSB was to never to disturb it.

It is the Germans that are being portrayed as not using DSB's anymore. (I haven't been able to get ahold of my cousin to get him to check into this for me) but from what you discribed they are not realy running a DSB in the true sense. they are manipulating it to drive it closer to a bacterial driven bed than a "critter" driven bed. So same name but two different animals.

Steve

[kari]

Steve;

What do you figure with the partitioned SB idea? Are you striving for nitrate reduction or other benifits of a SB like feeding or maintenance cutback solutions? My thoughts are getting off track.

[StirCrazy]

personaly I don't feel that feeding from a sand bed is a reality anymore as stated befor there have been saying that with the limited sand bed bio diversity in our tank the plankton produced is the wrong type or of a insufficient amount.

So my stand now on a sand bed is that it should be used and a nitrate reduction system and changed out at regular intervals. as to how long thoes intervals are I am not sure but I would guess between 2 and 4 years.

now seeing that it will be running for a significant amount of time it is inevitable that it will be popluated with creatures and intourn supply the rest of the system with some sort of life also.

as for partitioning if you are going to do it with one bed that would work fine, but you might want to set up 3 partitions and fill them all to start with. then each year pic one and replace it. this will give you a 3 year turn around eventualy on each partition which should work fine as most people who have had problems see them in the 4th and 5th year it seems.

Steve

[powerreef]

Its a tough debate. DSB's are very forgiving for the new tank and new user. They give the reefer an easy way of avoiding maintenance and not being punished.
I fall on the Nay sayers side, but I do see some advantages to a sand substraight. People who use DSB's use them for 2 basic reasons. One is for denitrification and the second is the bug life that it contains. These are 2 good reasons but a DSB is not needed to achieve them. I will elaborate a little more below. The inherant problem with DSB's is that they dont process everything. In reality they only process nitrogen based products, this would leave everything else unused and thus still in thier. Because our tanks have a bottom, this unused stuff piles up. As it fills (and nobody knows how long that takes, it has to do with feeding ammounts and husbandry) it drives the anerobic nd aerobic zones higher in the sand column, and because thier is a surface the upper zones just keep getting smaller and thus loose thier filtering compacity. Another huge problem and probibly the one most reefers encounter is the inability to deal with Phosphates. Concidering that all life in the bed carries phosphates and the simple PHosphate cycle of an argonate based sand Phosphates will leach back into the tank. This is where you see folks having problems with patches of algae here and cyano over thier and so on. An endless cycle of algae blooms.
Nitrification and 99% of all bug life lives in the upper aerobic zone. All bugs with the exception of bacteria/enzynes and protozoas need oxygen to live. So here is the way nitrification works in your bed.
dinitrogen is reduced by reduced dinitrogenase (which uses a coenzyme containing iron and molybdnym to carry out its reducing activity) to form dinitrogen dihydride (requires reduced dinitrogenase, 4 protons and 4 electrons)
dinitrogen dihydride is reduced by dinitrogenase to form dinitrogen tetrahydride (requires reduced dinitrogenase, 2 protons and 2 electrons)
dinitrogen tetrahydride is reduced by dinitrogenase to form 2 ammonia molecules (requires reduced dinitrogenase, 2 protons and 2 electrons). Sounds complicated by its a pretty simple process with nitrate as the end product. From here nitrates are brought down to the anerobic zone (a thi layer of both mixed oxygenated and anoxic zone. Now bacteria once again reduces nitrates to nitrogen gas. The bacteria that do this are facultative (means they consume oxygen first and when it runs out they go after nitrate ..basically). So once it is converted to gas the movement of bacteria and critters allows the nitrogen to off gas (the little bubbles you see in the bed).
From this point thier is nothing in your bed that does anything for your reef tank. These 2 zones can be fully operational with only a 1 1/2 to 2 inches of substraight, using either oothilic or even CC.
Now on the down side of this in the deeper zones we have a suphur cycle, iron cycle and a varity of nasty operations done by infuana that will never benefit the tank in itself. So why have it????? Thats why if one feels the need for sand in a tank 1 1/2 to 2 inches is more then enough to do everything you want. When the build up of things that are not nitrogen based occurs one can simply syphon out the entire sand bed, and thus rid yourself of any long term problems. People argue that it will kill your nitrate reducing bactering, this is simply not true, they are facultative and will simply consume oxygen until once more it runs out in the bed (very quickly) then they will revert to nitrate once again.
On the remote DSB, been thier done that. Bottom line is that it is not needed. A shallow bed will do everything you want, with out having to do the big nasty down the road. Also if you choose to set up a remote make sure you have a real long ammount of contact time, or it will turn into a settling tank in a hurry. IMHO a remote refugium with a 2 inch bed of sea floor and macro's are more then enough to take care of any dentrification you will ever need. Lets not forget the L:R that does the same thing .

Anyway sorry for the rambling

MIke

[StirCrazy]

Hey Mike, I was under the impression from Randy, Bomber and my own experence with fresh water tanks and DSB's that it was the bottom level (the anoxic zone) that actualy did the final nitrate to nitrogen gass conversion.

I have been running a DSB in my fresh water tank for 3 years now but I also have a ton of plants in there which help take the nasties out of the sand bed, could we set up a salt water plant remote bed that would work the same way?

I don't want to use macro algae or algae period, as it alwasy finds its way into the main tank but maby some grasses or other rooted plant would work.

Steve

[ryan_p]

I was sure that I was going to go with a DSB but know I am faced with a good arguement for both and really don't know what I should go with. I have the advantage of knowing that I will be having to tear the system down in 2 - 3 years once I finish school and relocate (victoria, probably). So if i do encounter a reason to change/clean the sand bed it can be done at this time. As someone said earlier, dsb's are more forgiving for the new reefkeepers. So I still lean toward going with it, but with some apprehensions. If you were going to be setting up a tank (46G) knowing that it was going to be moved in a couple years, what would you do for a sea floor? I like the idea that Kari had about seperated chambers for dsb's in a sump/fuge, but I probably won't setup a sump for a few months.

[powerreef]

Stircrasy this is they way it works. The bacteria that consume nitrate also consume oxygen. They will only consume nitrates once the oxygen is depleted, so for that you could say it need to be anoxic, BUT, they aer also the first in line and inhabit the zone that lies between aerobic and anoxic. A zone we call anerobic. So as this relates to the DSB thingy we have a 1 to 1 1/2 of sand for the aerobic and then 1/2 inch for the anerobic then 4 inches of anoxic dead zone. So to answer your question nope the nitrogen off gassing does not occur at the bottom of the anoxic zone, it occurs in the anerobic zone.
I have been running a DSB in my fresh water tank for 3 years now but I also have a ton of plants in there which help take the nasties out of the sand bed, could we set up a salt water plant remote bed that would work the same way?

Well most folks call that a refugium and it does do a pretty good job at nutrient removal. However algae cells are very leaky and for every percentage they absorb they leak out a good quantity right back in to the water again. Seagrasses are alot less leaking but also have some light reuqiring needs, but If I was given a choice it would be the grass for sure.

Ryan it all boils down to maintence. If you simply remove the detritus from your tank with a simple Syphoning you dont have to deal with it. Poof its gone, nada, no cycles no problems just gone.


Mike

[StirCrazy]

However algae cells are very leaky and for every percentage they absorb they leak out a good quantity right back in to the water again. Seagrasses are alot less leaking but also have some light reuqiring needs, but If I was given a choice it would be the grass for sure.

Mike

exactly that why I want to do it with grasses instead of algae. also with grasses you get the root system that will help clean the junk out of the sand extending the life of the bed.

I have a refuge right now but it is got bug growth only, so it 2" of fine sand, 2" of coarser sand on top of that and a bunch of rubble. I do not light this one at all. but I would not have a problem with making another one with a few floressent grow bulbs over it to light up some fast growing grasses.

Steve