Matt I kinda believe its the only way to feed these such animals without fouling the tank water. Most filter feeders with eat what ever floats in the water, detritus/waste/excess food. But thier are certain filter feeders that require Phytoplankton, since phyto is almost pure Phosphate regulating it in our tanks is a good thing. when target feeding these critters make sure they get some good time with the food around it.
Mike