Someone correct me on this or not. I was looking at Frontosa pics, and in none of them (I saw many) did this fish have a fat belly. None of the healthy ones had cave bellies either, but for the most part, they had flat stomachs. I have two jurupari which are around 5", and I grew from 1". They are extremely healthy, heal quickly from injuries, have great color, and eat like pigs. However, other than right after a big meal, they never have full stomachs. They tend to be pretty flat. Same thing with my large frontosa. She is around 4.5", very healthy, colorful, vivid, etc, but tends to be flat bellied unless she has just eaten. My oscars and firemouths, on the other hand, seem to be bursting at the seams even when I don't feed them for 1 or 2 days.