Banghaii(sp?) Cardinals are a good choice. I cant get mine to quit breeding and with a little effort, you could have quite a few survivors. They are mouth brooders and the male carries the eggs & then babies for a total of Approx. 6 weeks. When you see the babies swimming around in his mouth(you have to watch closly) you can put the male in a net breeder or a seperate tank until he releases the little ones. The babies feed quite well on live baby brine(feeding the brine just before feeding). I have had alot of success with these guys and, as bad as it seems, I just quite taking the male out... I have had only a couple survive natural release. In nature, they release there babies into a long spined urchin where they are somewhat protected by the spines. I havce also had my cloens breed 3 times and have had ALOT of babies, but to be honest, I havent had alot of success with rounding them up after hatching and they have only survived for a week or so. Hope this helps.