Rabbit cohabitation

Rabbits are known to be territorial animals. They love to, as a matter of fact, protect their space from intruders. This is prevalent with the grower and adults, though not very common among the weaners.
Recently, my grower rabbits that have been staying together all of a sudden has begun to fight themselves as an expression of dominance.

Now, in the absence of adequate space at the farm, is there anything that can be done to manipulate the animals so they can cohabit peacefully without any form of cannibalism?
Well, I have been thinking of the use of onion to make the animals smell alike. Though I am yet to try this.

Any advise on this? Please share your thoughts.