What other fish are in the tank with them? Honestly if they do not live with other predatory fish I would put the cave with the daddy back in the tank. The male pleco watches over and raises the fry until they are big enough to venture out looking for food after their eggs sacs have diminished. Plecos grow VERY slowly so keeping them in a breeder trap that long and keeping it aerated etc.. could be a pain. Even in my tanks that have fish that eat fry I usually just let them go and at least a few if not a good bit of them survive by hiding in plants and caves. Good luck with them. Baby plecos are cute and a lot of fun.