IMO, BB's not the ideal setup for them [nevermind that zo frags all over the BB make a LOT more maintenance/siphoning/re-arranging to keep their area from becoming a detritus pit.
i totally agree with the whole deterius pit thing. although, technically......this could happen with a sand bed also...and therefore would be a much worse problem b/c the sand bed would suck up those nutrients, and basically would slowly seep them back into the water. (notice i'm not mentioning anything about a DSB, i'm gonna refrain from commenting on that as i dont know enough about them).
this is a problem i am currently dealing with, b/c i lost my diamond sand sifting goby. while i had him, i couldnt put any small zoa frags on the sand or the fish would burry them in the sand. after he jumped out of the tank (go figure?? a sand sifting goby!?
) i got a little zoa frag crazy which basically covered my entire sand bed. two months later...bryopsis outbreak...and i still cant get rid of the darn stuff.
i kinda broke down my tank to clean most of it out a month ago, and i noticed that if i slightly stirred the sand bed alot of dark dirt would float up into the water. i did LOTS of water changes, and this still didnt help the situation any. my ultimate hypothesis (after reading alot of anthony calfo's articles) is the sand bed is polluted, and has got to be replaced now with a new sand bed. if i try to stir it up with sand sifters it will just release more nutrients into the water and make the algae worse.
my philosophy...if you are going to run a sand bed, is to do a shallow one, make sure you have good sand sifting snails and/or fish, and ALOT of them. make sure that at least ~75% of the entire surface area of the sand bed is UNCOVERED by corals rock (yes this seems extreme). my philosophy is if you can keep a good majority of the sand bed sufficiently turned over and clean, you will not have the problem of suspended nutrients building up in the sand bed, and in order to keep it turned over, you have to keep as many rocks/corals off the sand as possible to let those sand sifters go to work. to say the least...you gota be very creative with rock work.
in the new system i'm building, i plan to do a PVC support structure. so 75% of the rock work will be suspended at least 2inches off the sand, even in the back. i may even go 3 to 4inches off the sand bed to allow sufficient flow without blowing sand. shoot, i may even go BB in the back under the rock work, to keep sufficient flow, and sand in the front and sides only. this is hard to visualize, as its in my head the way i want to do it...and i'm not gifted in the realm of paint shop on the computer.
this is my philosophy, i'm not preaching it to anyone and i'm not saying its better than other peoples ways by any means. but this is how i was doing things, and will be doing things in the future after i set up my new system b/c i had tremendous success, even to the point where i couldnt get ANY macro algae to grow for 8months. needless to say it makes a zoa dominated tank rather tricky with the logistics, and placement...b/c a natural looking zoa environment is a sea floor covered in zoas.
with a BB tank, and placing a zoa like reef floor across the entire bottom...the key to doing this has got to be some sort of spray bar network under all the zoa colonies/frags in order to keep that deterius from building up and causing pollution. maybe even laying PVC pipe with holes (the spray bar network), and letting the zoas grow over top of the PVC pipes...which would take alot of patience though to get a good looking tank.
lastly....i think the best means of filtration (besides a skimmer), is natural filtration, nutrient export, and taking preventative steps to prevent nutrient pollution/buildup in the first place, is the key to success. once your sand bed is polluted, its gone IMO. theres no good way to get it clean again and not pollute your tank heavily.
i know alot about chemicals and biochemistry (no expert by any means)...and to put it simply, IMO I think alot of chemicals to reduce algae/nutrients are stripping the protective protein coat from alot of softie type corals, causing bleaching, stunting growth/size etc. but, this greatly depends on how you use those chemicals and the dosage/time you use them, and your personal tank chemistry, which is why you see such diverse responses with people's experiences with these chemcials....so its hard to say X-chemical will cause Y-response to Z-coral in every tank, b/c again everyones tank chemistry is different. but again, solely my opinion, anyone can disagree if they want...i'm not gonna argue it.
i'm not a biologist, or marine biologist by any means...so i'm gonna stop there...
sorry for the long post/ranting everyone, hope i didnt put anyone to sleep. :lol:
