That depends on a lot of factors; the individual temperaments of the males, how much space you have in the coop/run (overcrowding will quickly lead to problems), and how many hens you have. The recommended ratio of roosters to hens is 1 rooster for every 10 hens. If you can't at least come close to that ratio, I would strongly recommend getting rid of one of the two roosters. In addition to potential fights between the two roosters, as they mature 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 for hatching and 1 rooster can easily handle 10-15 hens in that regard.