Okay, so I'm setting up my 75 gallon FOWLR tank and I can't decide on substrate as far as that goes. For DSB's, I've always had problems with these in the past, it always led to nitrate issues. Too much debris was getting trapped in the DSB behind rocks, and under rocks, and other inaccessible places, As far as regular SB's go, I don't want it to cover my entire tank, I don't want it under rocks and other areas where it would collect debris.What I was thinking was a sort of canyon look with live and base rock piled on both sides, then a shallow sandbed (around 1 inch) running through the center of the canyon. Then I will be using 5 powerheads and a good cleaning crew to keep any waste from settling behind and under the rocks, Also I will be getting invertebrates to clean and stir the sand to keep in from getting debris in it, I will throughly siphon behind the rocks and vaccuum the sand periodically. I will be using strong skimming, and strong overkill filtering(always good) to keep the water quality as perfect as possible,and of course added to the filtering is live rock.I thought this would be my best bet in keeping the tank very clean and healthy. If you think I'm going about this right or wrong please let me know, also let me know if my idea about doing my tank barebottom is the right choice or not(of course there will be a little sand to make it look realistic)for me.
DSB.vs.SB.vs.Barebottom
- Thread starter yellow tang
- Start date
What turnover rate where you running? How much rock were you using to how big a tank? How did you stack your rocks: openly or tightly together? Was blasting your rocks with a turkey baster part of your regular maintenance?
And someone please explain to me how you could get enough detritus building up in a DSB to cause a problem, short of something stupid being done to the tank...
To me it sounds like your problem was caused by poor circulation, poor rock structure, or poor/incomplete maintenance... This had nothing to do with the DSB, it could just as easily happen with any other substrate/lack of.
Personally... I love both bare bottom and DSB tanks... BB because it's so much easier to move, clean and you don't have to worry about sand storms from the water flow. DSB due to the de -nitrification benefits and the fact that it just seems more natural.
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Aside from a bit of mechanical filtration that you are sure to clean every 2-3 days, and some chemical filtration (phosphate absorbers and/or activated carbon)... "strong overkill filtering" is not always good, as it can become a nitrate factory if it's not cleaned regularly, and the fact that with a good skimmer, live rock and a decent turnover rate as it sounds like you are planning, it's just plain unnecessary, and a waste of money and electricity.
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If you had nitrate issues on a tank less than 2 years old, the DSB is surely not to blame. DSB's help alleviate nitrate issues due to housing anerobic bacteria. The "problem" with DSB's and why some people refer to them as ticking time bombs is that they can saturate with nutrients and detritus over time and slowly begin to leach back into the water. Most people that claim negative effects on their tank due to DSB report this happens after 3-5 years, depending on nutrient load, amount of sand, etc. Also, when a DSB is disturbed it exposes anerobic bacteria to oxegen which kills it. If this is done in large quantities all at once it can create an ammonia spike.
I run a bare bottom system or "berlin method 2.0" in my 80 gallon reef. Having no sand on the bottom of the tank is only one piece of this method. Very high flow, over skimming and open rockwork design are necessary. The concept of a berlin 2.0 system is that all detritus is suspended in the water column for the skimmer to remove. I would not attempt to do this with anything less than 50x turnover rate. If detritus collects in the tank either due to insufficient water movement or constrictive live rock design you are worse off than you would be with a DSB because there will not be a layer of anerobic bacteria present to help consume nitrates and it will require effort to try to get in an siphon out detritus from potentially unreachable spaces.
If done properly, it can yeild some pretty amazing results but honestly I wouldn't even think about doing it unless you are planning an SPS dominated tank. BB can provide the high flow and extremely low nutrient environments that SPS thrive in but LPS and softies would probably do better in other tanks and for a FOWLR tank like you are planning I think it is unnecessary. You could go shallow sandbed (SSB) or even DSB and plan on refreshing small portions of it every year or so.