Welcome to BYC. Glad you decided to join our flock. You need to thin your roosters down, not so much for them fighting each other but for the sake of your hens' health. The recommended ration of roosters to hens is 1 rooster for every 10 hens. As they mature and the hormones kick in, too many roosters will become very hard physically on your hens; over-breeding them, biting and plucking the feathers from their necks and backs, battering them, and potentially, seriously injuring them. The only reason you really need a rooster is to fertilize eggs fro hatching, and 1 rooster can easily handle 10-15 hens in this regard. Please feel free to ask any questions you may have. We are here to help in any way we can. Good luck in re-homing your excess roosters.