Not a dumb question at all - actually pretty good one IMO.
Some folks will shut off their main return pump when feeding. I do that exact thing when feeding fish and corals. Otherwise - any floating food in the water will be drawn into the overflow and off it goes.
I shut'er down, feed, insure corals get what they need, fish get the rest, crabs attack any bits that fall to sandbed.
Then after awhile - fire up the return pump.
Powerheads too - if you have a lot of circulation, although this does not cause problems with food entering the overflow, but can make it harder for meat eating corals and anemones to feast.
Fire up the powerheads if you have fish that like to chase down the food, and it's fun to watch'em eat.
Do not remove the sponge prefilter on your overflow - it's there to trap bits of food that otherwise will fall down into your sump.
Just keep this sponge free of excess food/detritus by cleaning it in a bucket of saltwater, and you're good to go.
