How often to freeze frozen foods?

I had been feeding frozen foods daily (brine shrimp or bloodworms). I
usually try to rinse them out pretty good. I think I'm a little happier
with my water quality now that I've switched to one meal of frozen every
other day. Will this be enough frozen foods for the fish?

I've got Rainbowfish in one tank...those guys are like sharks! I don't
think any food every hits the bottom, the weekly 20% water changes keep
everything in pretty good shape there. It's the Cherry Barbs in the 10 gal
that I'm the most concerned with on water quality.