You should really get him another tank. Something 2.5g+ would be sufficient. He also needs a heater because bettas are tropical wish.
Please don't breed him unless you have a place to sell 500 bettas to. Or have the patience to take care of them for months and the right equipment such as containers for them, food cultures, enough plant coverage for the breeding tank, a basic understanding of bettas, genetic knowledge, plus a 20g tank to breed them in! All these things are very important! If you don't even know your betta's basic needs you probably aren't ready to handle 500 of them.
