I think the best diet is as much as you can possibly stuff in their mouth. The advice I was given was something like "Feed them like a teenager at a buffet." I've also heard "borded fish breed" so the thinking is, feed them so much that they become bored with food. I use the reciepe MattW gives in his book for a homemade food, mixture of high quality pellets, PE Mysis, and Cyclopeeze.