Id like to know too, currently I have about a 2" sand bed, someone said i should only have about a 1/4", because it will produce a nitrogen bubble or something.
after a really long time the sand bed will store many bad things in it.... which is not healthy if released into an aquarium... it usually takes a long time to get to that point.. if you have a good sand sifting clean up crew u should be good...
There are many successful Barebottom as well as DSB tanks- I'm not expert so I won't try to get technical. You could always go the middle route and have a nice 1.5"- 2" sand bed. That way you get most of the benefits of having a subtrate, without the potential of noxious gas buildup that a DSB can have...
DSB Pros:
It is easy and works very well to remove nitrate from the system/reef for quite a long time.
It looks good! and allows certain critters and fish to have homes, .
It is "plug and play" reefkeeping.
MAJOR DSB CON:
DSB crash! because it boils down to this - after considerable time (years) the anaerobic/microaerophilic population of bacteria present at the bottom of the DSB push into the aerobic region of the DSB and begin to compete with the aerobes. Once this happens phosphate is released by anaerobic bacterial death as oxygen hits them and from the wake of two competing bacterial populations (anaerobes vs. aerobes) literally going at it for nutrients.
As for the other options:
There are many pros to going BB. The biggest one is that you are more in control of your nutrient degradation (removal of rotting waste from overfeeding and fish excretion). You can use lots of flow to get any macro-waste (dendritus) into the water column and have the skimmer remove it (skimming wet) or have it catched in a filter sock.
The major con is that it is an acquired look! that is not as aesthetically pleasing as sand to some reefkeepers. It also requires extremely good husbandry skills in reefkeeping and considerable experience to do well.
you mean half of the same tank would be bb and half DSB? I think that would look strange- and the sand would probably shift unless you kept some kind of divider...
Well i just finished reading all of this and that thread that ink blue posted and yes i am confused, I ended up putting in the DSB last night, about 3-4", and now I feel like taking some out. I've read elsewhere that a DSB is good for keeping Nitrates low, now you guys tell me it causes H2S, so it's a toss up for a DSB.
jhov a sandbed does its job.. after a long time is when people start to worry about it... some people on there site had there tanks with dsb's up for 5, 8, 10 years before the tank crashed and some of them are still going strong... once the sand becomes live if its not already it acts like a buffer and also can remove nitrates if its a healthy dsb...
see if you can grab a scoop of sand from somone whose tanks been up and running for a while - then go out and purchase some sandsifters like hermits, brittle star, etc. - you can usually find decent deals on a sand sifting crew online or maybe from a LFS or someone on MR..