DSB Cleaning
 

Im getting the tell tale signs of deep sand bed nutrient buildup: algae on the sand, reduced coral and coralline growth, etc so it's time for a teardown.

This time around I won't be doing a DSB but I would like to reuse some of the sand. What does everyone think about giving it a good rinse (salt/fresh?) and reusing or just toss it and replace?

Also where is a good place in the Vancouver area to get large'ish totes for temporary tanks?

TIA
Ron

Muh!

Ron, I don't think you can clean the sand. I kept about 5 pounds of my original sand during my teardown.

Forgive my ignorance, but why get rid of the sandbed? Low coraline growth might just mean low alk and calcium.

Re: DSB Cleaning
 

use all your old sand that you need to make it 1 to 2 inches.. sell the rest.

I did that and all the problems disapered, I don't think it is a factor of the sand its self getting pluged up but rather the bed getting full. Also having a shallow bed is no excuse for not having critters to maintain it, I have a fighting conch and two tiger tail cucs in my 90 and they do a heck of a job.

Steve

Beverly the thoughts are that nutrients (particularly phosphates) bind to the sand and then begin to release once it reaches a certain level.

FWIW alk and Ca are 3.0 meq and 400ppm respectively and NO3 is undetectable.

Steve what grain size are you using? Do you do maintenance on your sand bed or is it fill-and-forget?

I was thinking of mixing in some larger grain sand and start a vacuuming routine though I would be concerned about how that would affect critters.

all sugar sized, fill and forget , thats what I have critters for.

Steve

I'm with Steve, maintaining a DSB can be a chore, recent articles quoting a number of studies have shown that you get de nitrification in a 2 inch sand bed. Fill and forget sounds like a heck of a good idea. Although I love my tanks I also like convenient and easy.

Doug

Re: DSB Cleaning
 

What's the rule of thumb with tiger tails and amount of open sand bed per cuke? I've always wanted one but not sure I have enough open sand bed. (Waiting for the bigger tank first... :rolleyes: )

Ron, I believe that PO4 is irreversibly attached to the sand. An acid bath would fix it, but then your sand would dissolve. If you're going to tear down the tank, don't waste your time by saving $50 on new sand. @ bags is likely enough to give you a decent sand bed about 1-2 inches deep. Put your rock in first and spread sand around it.

Re: DSB Cleaning
 

not sure they were given to me but I don't realy think you need open sand bed as mine are never on the open sand be but rather snaking in and out of the rocks on the sand.

they came out of a 50 gal tank with little open sand bed so not to much would be my guess.

Steve

This is new information for me, can you let us know of your source as I have a DSB and would like to read any new information. When I was setting up my DSB the research I did pointed to organism extinction as the main problem with DSB's. The suggestion was to renew the organism culture in the DSB every year or so with new stock. There are places in the states which ship "kits" for exactly this purpose. Since these organisms are not covered by CITES shipping to Canada is not a problem. A properly set up DSB provides many benefits and few negatives. This is the best article I found explaining DSB's.

Your quoting an article by Ron Shimek, who is the most biased person available to comment on DSBs. Many qualified chemists have talked about substances binding to calcerous substrate. An example is the use of kalk to precipitate PO4 from solution. And since Ca is a cation and PO4 an anion, the relationship is obvious. To break this bond would require something with a stornger charge, like HCL. However, although a bath in HCL would remove the PO4, the size of most sugar sands would lend itself to complete dissolution in the time required to cleanse it. Large crushed coral can be successfully washed in acid.
Further "proof" for me is the fact that I had removed some of my sand, cleaned it, and replaced it back in the tank. ALmost immediately it started growing algae again. I believe this algae growth is due to the presence of PO4 adsorbed onto the sand.
As a note, I now have a 1.5 inch sandbed and no detectable nitrates present.

The places that offer these kits do not ship to Canada any longer. It has been this way for a few years.

What makes you say that a properly setup DSB has many benifits and few negatives? Ron's article? Or long term personal experience?

Oh my, I guess this means that eventually I will have to remove the DSB and the sand bed in the aquarium is enough for the job. Or will it be enough to remove the top few inches of the DSB every year and replace with new sand? The main question being does the DSB still perform denitrification even with the PO4 bonding? Thus changing the top few inches would take care of the algae growth on the sand.

My (wrong) thoughts also. I tried doing that, but the algae continued. The PO4 accumulation also inhibits coral calcification, which I did notice as well. Denitrification does continue (it is not a function of the media composition, only size) although the 4" inches recommended by Dr. Ron isn't required. The aragamax bag actually says only 1" required, and I have found this to be true. In fact, a tank with the proper amount of quality porous rock should have 0 nitrates.
I believe that most people will need to remove their sand when it hits the 4year range. This should also be a consideration when purchasing used sand. The bad stuff comes with it!!
What i did was remove all my sand, and I added 2 bags of new sand. I am so far please with the results. I have a large selection of sand fauna, 0 nitrates, and the tank is now 3 inches deeper than it used to be.

you don't think that had anything to do with the cat peeing in it do ya?


this is one area where me and Brad disagree (not to often you'll find that) but I think it was more a problem with the depth and the bottom areas of the sandbed becomming septic and causing compounds that would not normaly be formed in a non septic enviorment to leach back to the water colume. by reducing the depth you get rid of these septic areas and thus no bad stuff.

I don't think Brad can say for sure it was because he put new sand in or because he reduced his depth as the sand he had in there had contaminated stuff from another source :mrgreen: so he never tried just reducing the depth as he HAD to replace his sand.

Dr ron's original theorys were good and work in the Ocean but even he admidts that in the hoby we only have 1 or 2% of the different types of critteres needed to make it all work properly, and for the past few months he has been backtracking on his whole sand bed theorys and trying to blame everything else like heavy metals and different brands fo salt for the sand bed failurs that were set up to his method.

Steve

I don't know if DSB's were the "trend" when I was doing my research but that was the suggestion all over the web. Unless I read all the wrong websites. My tank is only a few months old and thus is still going through the various algae bloom cycles as I didn't have the space to cure the LR properly before adding it to the aquarium. This resulted in lots of green hair algae growth. My green algae bloom is over and now it's into the red algae bloom. I'm just trudging along with my normal maintenance and every week the tank looks better with less nuisance algae.

I've had 0 nitrares since a few weeks after setup, lots of healthy macro algae, and copepod growth. Corraline growth is good and coming along nicely. Every week I pull out more hair algae, and it's not growing back. The only thing I'm worried about is Valonia, but I figure once all the excess nutrients, due to the hair algae die off, are exported it will be better.

I'll post my success/failure after I finish adding all my planned organisms. But don't hold your breath, that could take years according to my plan. :smile:

I guess DSB's were a trend when I did my research. Atleast I'm ok for the next 4 years or so :rolleyes: , then I'll pull out all my sand from the DSB and use that area striclty as a refugium instead of a regufium/DSB combo.

is your bed remote from the main tank?

Steve

Yes, it's a partition in the sump. About 20G where I have a 8" DSB and also use it as sort of a refugium.

Steve, you'll recall that the right side of the tank, which was the worst, had been reduced over 2 months to half it's original depth. Even when it was less than 2 inches, that area continued to grow the brown slime. You're right though, I'll never know for sure what it was about the sand that caused it.

There are currently a couple of long threads on RC dealing with these issues. Not being computer proficient, I am unable to provide a quick link. I recall one being labelled "DSB Heresy" or something of that nature. There is much discussion about the "standard" DSB theory, which is often attacked. Some propose modification to accepted DSB "practice", including the management of anaerobic/anoxic zones within a sand bed. There is also discussion of phosphate binding.

Interesting for both its content and the heated discussions/personal attacks among the proponents of conflicting theories.

Cheers.

Trevor

Yes those RC threads can take on life's of their own. Unfortunately lots of good info gets lost in the works.

IMO the main point to take home from them is that total bio load is important whether you have a fish only setup or a 'balanced' reef system, bare bottom (not the kind that you sit on :eek: ) or a DSB. The odds are that without some form of intervention beyond adding food, Ca, Alk, and top off water, the system will eventually crash. For an aquarium to be a self balancing ecosystem like a real reef then they would have to be a, well, real reef.

I think that I will be replacing my sand with a shallower bed of coarser grains and place less emphasis on critters and more on manual labour. May as well give a different method a go for 3 years and compare.

Out of curiosity, did anyone with "PO4" contaminated sand, acidify it to disolution and then test for PO4 to see if there a significant amount bound then released?
John

Okay, I can understand that in some reefs nutrient buildup would be a real problem, especially if there is no natural means of export, such as a refugium or macroalgae in the display tank. MA, like house plants, plants in a planted FW tank, etc., need P,N,K for proper growth. P = phosphate, N = nitrogen, K = potassium. I'm thinking that if a tank has macroalgae somewhere in the system, nutrient buildup shouldn't be that much of a problem, even for phosphate which MA would certainly use.

Just a thought, anyway.....

Ok sence this won't die :mrgreen: I will explain my point of view on the phosphates issue for more clarification.

if you look at natural process of binding in the ocean you will find that Mg grabs the Ca moliques and basicly seals them off by binding them untill the Ca is nutraly charged. This has been pointed out my RHF and a few other chemists.

the problem where I could see phosphate binding to Ca is if your tank is Mg difecient and Phosphate rich, you might have phosphate binding because there isn't enuf Mg to do it.

but if you have a proper range of Mg you should get Ca that is "Mostly" Mg bound because Mg is much higher on the reactive list than phosphate. (I am going off memory on this one so if some one has a reactive eliments chart that shows different let me know)

Steve

Hey Brad, what would one use as a source of HCL? Bleach? I have some coarser grains mixed in that I might try to cleanse.

One thing you can count on if Dr Ron says the moon is blue, in a year he'll say we misunderstood him or, he was misquoted. OR, he may even admit he was wrong but the fact will still be, his mind has changed, so what he said a year ago, is out, the new gimmick is.....

Just my two cents worth. I'll not mess with a DSB anymore, I didn't have trouble with mine at all but I know I can get good filtration in a 2 inch sand bed because I did it, when I took my refugium out of the picture.


Doug

2 inch is still a DSB, just not as deep as a 4" one.. I think to not have a DSB you have to be shallow enuf that you are not getting denitrifacation as a result of the depth.

Steve

hmm good point.. so.. .. oh well I'll not bore everyone with another poll of, what constitutes a DSB.. 1 1.25 1.5 1.75 or 2 inches

lol.. it works, I'm happy and it's about half the price as twice as deep.. funny how that works out

Doug