I've had a this tank going for about 4 years. I have tried to keep all kinds of things in it and besides my fish and a kenya tree nothing seems to hang around. It seems my nitrate don't like to hit the zero mark. At one point it was staying at 160. I have add a cpr hang on ref and that helped allot Got rid of the little bit of crushed coral and added figi sand and that brings it down to 40ish. I am working on getting a sump and a new protein skimmer.I change the water every 2 weeks or so. Feed only a pinch at night. Have a good clean up crew. have a canaster filter that i clean out on a reg basis.All my other water specs are fine is there something I am missing. I see all the pics of you're tanks and I am in awe. Any help would be great