I have this problem too. I have 2 Roosters and have had them for about 1 1/2 years. Eventually, the stronger Rooster will become the one that mates with the hens while the less dominant one will be a glorified security guard. But what they will do is trade off responsibility. I don't know if you free range or how big your property is, but the dominet Rooster will walk your property line while the other rooster will walk side by side with the hens all day. When a hen wants to roost and lay, one rooster will escort it to the coop and wait until the hen is done and then escort it back to the flock. This is how they establish the pecking order.
If they are young and you stop the agression against eachother as it happens, then you can control and even change the pecking order. But this takes a strong person to grab the rooster and tame it and it takes time. Its not overnight but within a few weeks you can teach them that you are the boss and you are determining the pecking order if you are consisent. But 2 roosters for 3 hens is a bit too much, you need to get more hens or the roosters will take out all their mating agression on the small flock. I think the ratio is one rooster for at least 5 hens.
For me, I like having 2 protectors, but I have an acre of land to protect and about a dozen hens. My roosters are agressive, but they haven't lost a hen yet! So I decided to keep them.