conflicting opnions on dsb

[alrmc4]

i have read that dsb must be maintained by stirring them and that the sand slowly dissolves over time and must be added to. and i have read that you never stir the sand bed as nasty things are in there that you could stir up so what is the best way to go?

 

[reefrunner69]

When people refer to stirring the sand bed, they are referring to the turning of the sand done by the critters in the bed. You should never mannually stir your dsb. Copapods, isopods amphipods bristle worms, peanut worms, etc...will do the job for you.

 

[alrmc4]

actually the article said stir gently with a dowel

 

[reefrunner69]

Hmmm, who wrote the article? I'd like to know whose writing to avoid. Stirring a DSB in that manner would have seriously bad effects on your tank, is it possible they were referring to a shallow sand bed?

 

[fishfreek]

Very interesting indeed.

The whole theory behind a DSB is that you have different zones simular to a plenium system. The upper zone helps with the ammonia and nitrite removal. Further down within the sand bed there are areas that are lower in oxygen content. And only in these low oxygen regions can the nitrate removal occur. If you manually stir the DSB then your oxygenating those oxygen low regions and in effect removing the sand bed's capacity to rid your tank of nitrate as effectivly.

The reason for the sand sifting creatures is so they can keep the upper layers rich with oxygen and at the same time allow the nitrate particles to slowly make their way down to the lower regions of the sand bed.

 

[loganj]

I have read, and I can't remember where, that lightly stirring the top layer of any sandbed will release bacteria and other critters that corals can use for food. I believe they were referring to only the top 1/2" or so of the sand. In my coral tanks, I have a DSB in the bottom tank and only about 1" of sand in the top tank. I stir the top sandbed occasionally to feed the corals. I think the safest course of action would be to leave the DSB alone though.

 

[alrmc4]

thanks ok new thought what about a 2 inch sand bed in tank and dsb in the sump/ref? maybe i am mixing up all the research

 

[reefrunner69]

There would be no problem, and possibly some benifit to manually stirring a 2" bed, the dsb in the fuge would need to be left undisturbed.

 

[mojoreef]

I would have to go with Kevin on this one. If you run a DSB in your main the absolute best you could hope for (if everything is running perfect) is the processing of nitrogenious waste, betond that it wont process anything and will eventually become a sink. If its in the refugium you could at some point remove it and deal with it without screwing up your tank. If you are going with a 2 inch bed in the main I would suggest going with a coarser grain size, say Crushed coral. This way you could simply vacuum out the CC and remove all harmful toxins Ie nitrates and all the other stuff a DSB wont touch.

good luck

mike

 

[HoopsGuru]

The idea of a DSB becoming a "sink" is completely untrue and has no factual evidence supporting it. In a properly set up deep sand bed with a variety of detrivores and other critters, there is no end product that hides itself deep in the sand waiting to attack in the future. There are sandbeds dated as old as 16 years without any problems whatsoever. Several friends of mine are well over five with still no detectable nitrates. My oldest is reaching two years, and there is not a hint of nitrates, excess detritus, or nuisance algae.

 

[mojoreef]

Hoops I would love to debate you on your statement Its a Physical impossibility for it not to become one. Even the so called DSB guru Dr. ROn says it will. I dont want to hyjack this thread but purhaps if you feel like a good friendly debate I would love to talk it over with you.


MIke

 

[michealprater]

I would love to see you guys debate, and I am not discouraging it. However, It will be a endless debate as I have seen so many times. The only thing I have learned for sure, is that niether side of the debate have any "hardcore" evidence to base their argument off of. I would love to see someone prove the point beyond a shadow of a doubt, however this is yet to be done by anyone, including Doctors and chemists.

 

[Guest]

Ok, I'll get in on this:

The only thing I have learned for sure, is that niether side of the debate have any "hardcore" evidence to base their argument off of

I have to agree with MP. I have read so much my brain hurts and it is true, there is no conclusive evidence either way. I have read Dr. Ron's articles and have seen none of them that ended in saying that DSB's are bad for future. He always refers to them as having the possibility of OTS. I don't think Dr. Ron is the ultimate authority on them either. You show me one DSB with the proper amount, or as close as you can get to all of the detrivores and inverts you should have, that crashed because of the DSB in itself. I don't think you will find one. I don't mean because of anything else either. It has to be a direct impact from the DSB. I still don't think you will find one.

 

[mojoreef]

I here ya. I am not a big believer in OTS either. and I dont really believe that a DSB will cause you tank to crash. However it will eventually stop working. A DSB only processes Nitrogen based products. Where does everything else go???? straight to the bottom. As it goes thier it begins to fill, as it fills you loose your arobic zone. Lose that and the bed just stops working. Its really just physics. How does it take, well that all depends on your bio load and feeding habbits. I have seen many stop working, so has Ron.

Proving it easy but I have also seen many of the endless threads, so no problem I dont want to distrupt the board.


Mike

 

[reefrunner69]

I personally don't have a problem with the debate. I don't think anyone will convince anyone else, but I think having both sides of the argument out there will be beneficial to all. It gives the hobbyest the info needed to make their own decision from an educated standpoint.

 

[alrmc4]

i agree rr it is a debate i am following closely so that i can make the best informed choice possible...thanks for the fair honest no name calling debate

 

[HoopsGuru]

I think it is virtually impossible to provide any clear conclusions of a DSB that suddenly "stops working". There are too many variables that would need to be described that could cause a problem or failure to occur in ANY tank setup. Personally, I don't believe as timbo stated that you can identify a DSB crash as being related to the DSB itself unless there was an inadequacy created by the hobbyist. I think most of these crashes have been unfairly labeled on the DSB when there is a much more definitive cause in a lack of bio-diversity, overstocking, overfeeding, etc.

While I give a lot of credibility to Dr. Ron for his invertebrate studies for which he is educated on, I do not follow most of his other speculations that he has created for the hobby as I have seen several without any merit. As I stated before there is absolutely no credible evidence or study proving that a deep sand bed will become a "sink". And there is also no evidence that is can last forever. However, I look towards the success of people like Rob Toonen who have successfully had DSB's in their tanks as old as 16 years, as well as friends' tanks that are approaching 10 years.

If their is in fact a problem with an end material that has nowhere to go, then indeed EVERY system will eventually fail. This is assuming that some end result indeed gets bound up in the substrate, rock, and animal tissue. If anything, I feel most secure with the longevity of a DSB over others because there is such a diversity of animals consuming the different forms of matter in the tank. My oldest DSB is approaching 2 years, still young by some accounts, but I see no evidence of any future problems. Time will tell if this will hold up, but until it happens in my own tank that I know exactly what went on in, I am not going to lend any weight to anyone else's anecdotal evidence stating the contrary.

 

[Hara]

Can you tell me of viable alternatives that are guaranteed to filter my tanks and never crash or outlive their usefulness. (I am not being sarcastic incidently, this is a legit question)

 

[Guest]

Sure, a complete filtering station. one 4 times the size of the main tank. Something like Sea World?

I don't really know the answer to that question, I was just thinking at the time about the major aquariums and how they maintain their inhabitants for 20 or more years...

 

[HoopsGuru]

I believe the best answer to that is simply, dilution. There filtration systems are larger, but to my knowledge they are just more efficient, yet producing the same end result. The difference is the amount of water they contain. For example, EPCOT's aquarium is estimated at about 6 million gallons of water turned over every 2 1/2 hours. As Anthony Calfo explains, "dilution is the solution to pollution."

Until we are able to do this or have a system which completely exchanges the water as some coastal aquariums do, I feel the safest with a DSB right now.