I think you want to keep the bottom but sounds like you want it bare
I think it probably makes no difference at all. I do think sand harbors a bunch of junk (stir any from any established tank) but just because its there doesn't mean its hurting anything. I see no reason why bacteria populations wont process these organics when they break down any differently than detritus breaks down in a bare bottom. there's more of it with sand but bacteria populations compensate with supply and demand. I dont think it will fix any algae problems at all. the only thing no sand will fix is sand on the diatoms which in some tanks never goes away completely. no sand solves that problem. I do keep sand in the sump and my main reason for removing the sand fom the display was it was hard to keep from blowing around with the high flow I have. I can go full speed with the magfloat, point my powerheads where ever I feel like it and basically do anything I want in the tank without clouding up the water with sand or creating a sand storm. I believe sand harbors alot of beneficial creatures and surface area for microbials. In my case the return pump has to deliver the larvae ect that helps feed the tank but there's alot of life in the little sand area I have in the sump (DSB too). NO sand anywhere does make for an ultra clean set up but I dont think its any more effective biologically at dealing with nutrients. there's no substitute for traditional methods (lower bioloads, larger water changes, increased skimming, less feeding, phosphate binders which would be my first means of action and not so traditional but bacteria driven carbon dosing systems).
this was one of the last pics I took with sand. I just siphoned it out during water changes. took a few times and moving some rock. I had a very shallow sand bed ( 0.5" if that and non functional, just for looks) so taking most of it out at once was no problem. if you have alot take it out in layers over time.
directly after removing. I still run the same skimmer now. I dont buy the super skimmer theory either. skimmers move dissolved organics. No amount of keeping detritus suspended is going to dissolve it. for that I'd think a filter sock would be more effective though I use NO mechanical filtration. I'm not saying skimmers cant pull solid particles (dead amphipods end up in my regularly) but thats an insignificant portion of their function IMO. bare bottom or not particles will find a place to settle and have to be siphoned out. you wont find as much as a sponge anywhere in my tank, pumps, overflow box ect. I do think a good skimmer is needed (going thru all the trouble to have a clean bare bottom might as well have a good skimmer). "good" is up for interpretation. I would call mine just adequate for my tank. Not great, not bad. not oversized or undersized bare bottom or not. I have you basic small octopus with the current pinwheel. very simular to the current NWB-110 (its called a PS-120. not out very long).
and recent (I had a little green algae with sand, alot of red turf down the line witout so I dont think it makes a difference. I'd rather have the green lol...even bryopsis..red turf is HARD to irraticate).
