4 six week old ducks attacking eachother

[JoannaFowl]

Hello! Im very new to taking care of ducks, we're not even sure of the genders yet. We just started moving the ducks outside in their coop every once in a while but other than that we've had them in our room with us as it's been cold and rainy lately.
Last night we noticed that one of the ducks was bleeding on either side, so we watched for a while and saw that he was being bitten by the biggest duck. We separated the violent duck from the group. Then this morning we noticed one of the other healthy ducks was biting at the hurt duck once again.

We ended up letting the three healthy ducks out into their coop and took the hurt one into our room to watch and make sure he is okay. When we checked on the other three outside. However, the other two ducks that ended up getting hurt as well by the biggest duck. He is the only duck now that isn't bleeding from his feathers. From what I can tell its their blood feathers that the largest duck is attacking. We have the largest one separated for now, but we dont have enough space to have all of them apart so the other three are together and we're just hoping they dont continue attacking each other.
We check on them frequently and for now they seem fine but it breaks my heart to see them all busted up the way they are. Is there anything i can do? We have them outside, we feed them high protein foods and they get fruits as a treat every once in a while. This literally just started yesterday Im really upset and dont want them hurt anymore. Any advice would be greatly appreciated.

 

[Cnstory78]

I am new here but have some experience with ducks. I know they can be aggressive and usually sort it out on their own but I don't believe I have ever had any draw blood (though today I thought surely 2 big rouens would drown my Pekin hen, they have been together over a year now and we finally have a hen brooding!) Maybe separate as much as possible and reintroduce one at a time? I hope someone has better answers and your little ducklings get along better.

 

[JoannaFowl]

It has gotten worse now, we had the three injured ducks together outside and they have gained up and severely hurt the initially bullied duck. He is bleeding badly from his back now. We bought something this morning that was supposed to make them stop biting at each other, called pick-no-more and it seems to have made it much worse on him. Im at my wits end here i cannot have just one closed off in the coop and the other large violent one in my room please i need more advice.