It may seem that live is less likely to produce the inevitable ammonia, but I believe it is easier to over feed with live. Fish will eat less in pellets than in feeders,(gram for gram). There is more usable nutrition in a quality prepared food, generally speaking. Less needed to feed, therefore less waste.
I used to have feeder goldfish on a tank with a walking catfish.. Anytime "she" ate a feeder, the water would get nasty fast. Flake or pellets, not so. I think there is just more undigestable waste generated by eating a whole fish..
