I've got a total of about 10 - 12 fry between the 2 tanks. They start out very small; maybe a mm long or smaller. Supposedly they hatch in a day or two. Since mine were in the same tanks as the other fish I didn't see them until they were bigger. I think I first noticed the first one in May and it's still not full grown. I have them in many different sizes so they must have been mating over a long period of time.thanks for the advice Nick. How many fry did you have make it to adults? and how fast did they grow?