i know, i have told them (the daughter goes to my school) to remove the parents, so the fry get eaten, and i have also asked them for fry, so i could feed by fish, but they don't have any impact on the population. The convicts are weak though, they started out with only 10, and have added none, so they are all inbred. But the last time i checked they had this huge monster that was 7 inches and he ruled the whole tank. but hopefully they will remove all the males or something and make it gender specific, or rehome every single convict to people who would use them as tankmates for bigger fish, or for some people who use them as feeder fish, and maybe they could start all over.