Mine are doing great with full EI and 75% PWC every saturday. It is more important to make sure they are getting enough food (they don't carry any reserve). I think most deaths are from starvation. They will take well to wafers. Just make sure that they don't have to compete for them (they are not good at that). I tend to over feed wafers to make sure they get their fill.

I have had one for about 10 months and the other for about 3. One of my favorite fish.