Fwiw my experience is limited. One problem that I've never actually heard mentioned elsewhere but which I experienced was skewed sex ratios. My first batch was a group of 12 1/2" fry. Upon growing them out I had 10 reach adulthood, all females! The odds of that are very slim indeed if the spawn they came from had any reasonable sex ratio. The second problem I encountered was because the fish really live up to the "crypto" portion of their name. They hide their spawning site as well as any Pleco. I'm certain I missed at least two spawns once I finally got some going, because I didn't recognize the meaning of the color change they exhibit. Once I did, every time I saw a female exhibiting the breeding coloration, I found a spawn. I have heard it said that they're very sensitive to water quality, but I'll have to admit to having missed 3 consecutive weekly changes on the tank I just found my last spawn in. The tank is heavily planted and fairly lightly stocked and "sensitivity" can certainly be relative. I find the fry easy to raise but slower growing than most other Cichlids I've worked with.