The bio-pelletes need to be tumbling, not stagnant. Flow is very important. I have either a MH600 or MJ900 running mine. The Phosban 150 comes with a valve that you connect on the outflow side to control the flow. Mine is about 2/3 open.
Many folks do NOT use zooplankton or any supplemental feeding for their sps
corals. I personally feed about once a week with 2-3 additons to my normal tank feeding.