Males grow larger. Otherwise, gender differences aren't dramatic, males a little more color and slightly longer fins as they mature. As juveniles they're happy in a group, almost the more the merrier, and a group of 5, 6 or more unsexed juvies gives you a decent chance of getting a pair. Once a pair begins breeding they keep to themselves more. They still interact with others in the group, but a little less so, and are perfectly content as just a pair with other compatible fish. Ime unpaired females in a tank will pester the pair or pairs, trying to get the attention of the male. Two pair can work in a 75 gal tank or larger if you arrange the tank so each pair gets their own area for spawning, mine liked an area they could defend-- whether rocks, driftwood, etc. Males and females shared mouthbrooding and would even trade off holding fry while the other parent fed.
I found them easy to breed. Even in a community with Heros rotkeil, wild Peru scalare, congo tetras, L200 plecos, they did a good job protecting fry until I was ready to move them for growing out. I found them to have robust health in clean water, good oxygen, good food. Pretty pH tolerant, healthy up to 8, probably. I've heard of them being kept healthy a little over 8, but I suspect, everything else being equal, they won't live as long as pH in the 7s. I fed Omega One and NLS back then (I stopped using Omega One when they went to a cheaper formula), freeze dried mysis and freeze dried blood worms occasionally.
They start coloring fairly small, 2.5-3 inches if I remember correctly, adult color in about a year, though it can improve a bit more in their second year.
Nice fish, I enjoyed them and could do them again.
