The theory is: IF you QT all your fish BEFORE intro. to the main tank, the main tank should have no problems. Hince, hopefully never having to catch the fish in the main. To catching fish, the only way I got mine out in a 75 was to remove the rock, you can try the net when feeding, but I swear they get wise to that. I learned my lesson, it only takes 1 time and then never again. Qt'ing for a few weeks is sooooo much better than breaking down a tank (but sometimes you get better aquascape, but still not worth it). Also on another note, if you have a very mild case of ich, have you tried the garlic method? (assuming that it is ich). That could help them "kick it". Just a thought. HTH