Lots of ways to deal with it. If you have a way to dry & make pellets, that is the best. Otherwise, acclimate the tilapia to the grain, then turn off the filters, feed then what they will eat, and turn the pumps back on. The stuff is messy as-is and will foul up the works if you don't turn the flow off for feeding. Tilapia learn quickly, so this is a 5 minute process if you don't over feed.