I target feed my Tubastrea brine shrimp (about a tablespoon worth) every other day. They are growing rapidly. That's two tennis ball sized colonies. If you turn off your major power heads while you feed them you can target feed each polyp, which is necessary since they do not "share" resources between them like most corals -- ie, each polyp is very much on its own for food.
Cheers!
--Sean--