I have a ~1.5-2" white sand bed. Did it for looks/bacterial filtration - and I like the look. Thought it was good as a "deep sand bed" for bacterial filtration - but have since learned that "deep" is like at least 8 inches. I've kept it for the look. I also had some guys at a nice LFS/Coral shop telling me that I should be careful placing my live rock on it because eventually the rock would settle and could sorta slip into the side and possibly crack the glass... which I always found to be an extreme take. And hasn't happened in ~8 years for me.
But - I've had SO many issues with nitrates and recently I'm thinking that this bed of sand is likely harboring those nitrates. What do you guys think?
I have a 40 Breeder with a good 4 to 5 inch dsb, hey it was all the rage when I set it up years ago, now they are more or less taboo. I was fine for maybe 5 years, and the last year and a half or two, I have been battling insanely high phosphates. Only the heartiest corals survive, so I wont ever buy anything, havent in 2 years. Ive tried reactors, phosphate removers, extra water changes, and it wont stay at all, cant even get it down to 2.0 on the api test. The refugium with macro algea helped for a while, but eventually had no affect.
I admit I dont vaccume the sand much anymore, so Im sure its the issue, so last thursday I removed an inch and a half of sand. And phosphates went at least 1 point down stayed all week. So I took about an inch yesterday, a week later, out, and my plan is just to leave an inch in there and a few inches under the live rock. I have an amazing Yellow Goby Tiger pistol combo, and they love the sand, I dont want to rehome them.
I have no measurable Nitrates, and thats part of the problem. But from reading they say if you remove your deep sand bed, watch your nitrates, mine havent changed so far. I got a reactor set back up with these specialized pellets for phospahte removal, and got the refugium back with some macro algea.
I think this will get it back on track. I havent seen Coralline algea in a few years in my tank. Its sad.