yep the skimmer will take out the phyto.......so when you feed the tank Dts which is a good idea for larger clams, pods, and some smaller clams apprieciate it, but like peabody stated its a great idea to target feed those expensive little guys with the bowl technique.........so shut the skimmer down feed the tank a small amont of Dt's then take the oppertunity to clean the skimmer, I feed my tank twice a week with DT's small amounts.......and I target feed my baby max twice a week on different days than i feed the tank....