The breeding was accidental...
I got a pair from DD and they have bred a few times, I found this pair in my over flow about 8 months ago, I left them there for about 4 months and then fished them out and put them in my QT, where they have been for the past 4 months...
I also have another pair (about 3 month-old) in my other overflow now...
I am not doing anything...they just seem to end up there on their own...once in the overflow, there just aren't any predators so they can grow up in peace...