Also keep in mind that you need a place to take the babies. Once you get a pair started, they really won't stop unless you seperate them. Am talking like babies and babies and more babies,. And male bns are territorial, so you should have plenty of space between the caves. And also, more caves than fish, because once the babies are free swimming, they will leave them in a cave, and move to another one and start again. I have 3 breeding males, and not sure how many females, plus even though I try to catch all the babies, I seem to miss a few, so they grow up a bit more, which my LFS likes, lol. I just let them grow out in the same tank with the parents, I lose some to my rope fish, but most make it so its ok.