Okay, thanks for all the good ideas. Here is my tank info: 20g w/35 lbs fiji live rock, argonite sand bed maybe 1", 65w smartlite (50/50 actinic/10K), 2 smaller penguin powerheads for circulation and red sea prism hang on skimmer. Ive got 2 small clarks clowns, bubble tip, xenia, yellow polyps...