My convicts were the stars of my tank! They successfully bread several times (I had a new batch of fry about every two months.) The male was very large, over 5" long and very aggressive. The rest of the fish in my tank ran away. He was a show off... swimming out in front when guests were over. He truly had a nasty attitude, so I liked him. The female was really finicky.. sometimes she's just hang out at the top of the tank and other days she'd be chasing the male around the tank. She was significantly smaller (around 2.5") but just as nasty when there's fry in the tank.
This is a picture of the baby fish about 4 months old. This is a 30 gallon tank. They were packed that dense. I sold them all (The guy at the fish store said there were more than 500 of them) for about $200. at $.40 that's a steal. When I sold them they took up 4 tanks and were all about .5 -.75 inches long. I sold them in batches - the smaller ones stayed at my house until they were big enough. I'm sorry to announce that both convicts died shortly after a move about a year ago and The fish in my tank now include only 2 of the original set of babies.