If the fish are still alive and one has ich, get a cleaner shrimp and get some parasite stop. This is a pepper based product and you must add it 2x/day for 5 days. Even if you flush the one with ich (I don't see a need to kill a fish without trying to cure it), you shouldn't add a mated pair of clowns until the ich is gone. It's already in your tank.
I had a fish with ich and did some research on it. If it's little white grains of salt, and they seem to come and go, these are dinoflagelates that encyst on the fish and then hatch, hang in the water column, then reproduce and encyst on the fish again. You need to break the life cycle. You can, once the fish are swimming again, lower the salinity, this will help break the life cycle, but the cleaner shrimp and the parasite stop worked for me. I did have to add a buffer up solution since the parasite stop can reduce your ph.
Don't give up on the little guys, give them a chance!