Anyone band their buttons? I was thinking about banding any that I had a hard time sexing or telling apart from others (ie, the whites, lol). I plan to keep in pairs, but, I have such a terrible memory that it would be easier for me to put a band on one of each pair and then just make a note on the cage or something. Any advice on it? Can you do it once they're full grown, or only as they're growing? Thanks guys.