I removed the aerator on my kitchen faucet and attached a hose for a time and cleaned the aerator. Now I cannot get the original one to screw back into the place without it leaking (well spraying mostly). Any suggestions on ways or tools to get an aerator firmly back in place?
Is there any chance you've cross-threaded it? If you're sure it's not cross-threaded, then I'd check for a missing washer or O-ring. It may have blown out of the aerator when you were backflushing it with the hose.