You can always set up a separate tank for the peeper.
Keep in mind that if it's a male, well, I'm fairly convinced that pound for pound a peeping peeper is the loudest critter on the planet. This is the number one reason I don't already have one of these adorable little critters, they hurt my ears outdoors, I'm afraid to be locked up with one. Be sure you can live with this possibility before committing to keeping it.