i have found that if you really get to know the fish, you dont need culling tags.
what i mean is, spend some time with your fish. get to know their likes and dislikes. find out what makes them tick. then assign them names like pete and debbie, maybe even dan or brian. its easier to remember a name when you have a face to put with it.
once you know your fish, you will remember who is who. when it time to throw eric the 2 lber back and put rob the 3.5 lber in, you will know what to do.