I find it very convienent to put the fish food into the sump and let the return (Mag 5) fire it up into the tank. Can the food damage the pump in any way? For instance, I just put some Mysis through there.
same for me i do that with mine i put my mysis in a cup of RO let it sit in the a couple of min strir then in the sump it goes fish go crazy and go chasing the food. its more fun that way than just droping in the cube