Ok how do I get my sand this clean (see video below). This tank has to be well established to keep this many fish. I know about CUC, sandsifters, etc. etc. etc. Some fish won't let you add any thing else to the tank. My purple dottie back wrecks every white diamond goby that I put in the tank. Is there any of siftinf gobies that I can add to the tank. or is there another way to add the goby??????????