I bought a yellow clown goby or coral goby depending on what you want to call it. I havent seen him eat yet, but havent been able to find if hes strictly a column feeder, or if hell also eat off the substrate. I have tetra marine sw granules which i crush to a powder for the little fish, brine, marine grazing block, and krill in a gel. Hes in qt with a firefish, who ive only seen eat out of the column. I have to really watch what i add, cuz its a barebottom qt and the ceramic rings to help the bioload will get overwhelmed easily