They will breed in either place with time, but if your serious about raising the live stock, a bare bones setup just for them is the best to ease the collection of fry. Not sure how much you've researched this, but it will take yet another system for grow out as you can't leave the babies with the parents, you'll need to culture rotifiers, and at first they need to be fed every few hours. There are some great books out there, I would highly suggest picking them up as I'm no expert, and you'll need a lot more complete guide than what you'll find on the web. It takes a LOT of time and patience to raise healthy quality fry. I wish you luck and keep us posted with your progress.