Theo & Benny had it out yesterday and there was a LOT of fluff hanging round where they'd attacked each other. Theo is orange and Benny is brown so I was able to roughly estimate that they both gave as much as they got.

So last night I seperated them with a clear barrier so they could still see each other, and ut both their litterboxes against the barriercause they hang out in them most of the time. I've got them together again now, in a much smaller space...hopefully forcing them to bond.

Any advice or suggestions? I obviously checked both of them for bite marks but couldn't see anything.

Hi!  Gosh I am sorry to hear about the fight.  It sounds like you've done a good job so far post-fight.  Since these two are having quite big spats, have you thought about using the L-shaped x-pen set up for bonding?  That way if they do get into another tiff one or the other can get away? 

X-pen bonding set-up (L-shape) http://www.binkybunny.com/Default.a...stid=31999

X-pen bonding experience http://www.binkybunny.com/Default.aspx?tabid=54&forumid=11&view=topic&postid=41219

How are they doing now in the smaller space? And how long of a period of time do they spend together? It sounds like they may need to be "stressed" a bit while they are bonding, to distract them from fighting, but if they are spending long periods of time together, obviously you don't want to keep them in a stressed state of mind. With my bunnies, I try to start the bonding session by stressing them slightly by taking them in a car ride in the same carrier, or by running the vaccum cleaner around a cage that they are both in.

You can watch out for the signs of agression mounting, like nipping or one bunny charging another, and then run the vaccuum or distract them with food to try to divert the situation.

They don't have any signs really before a fight. I'm bunnysitting them and so dont have a firm grasp on their behaviour and personalities. Unfortunately the owner has a bias towards Benny and so when she was telling me about them she put all the blame of recent fights onto Theo. After watching them I've discovered that it appears to be a combination and basically this happens:
1. Theo hops casually over to Benny, no attacking stnce
2. Benny flees
3. Theo sort of follows, it's not chasing but a more casual hop
4. Benny runs into a dead end, turns around and becomes aggressive, possibly out of fear.

I can't break this cycle cause Benny wants nothing to do with theo but Theo seems to really crave company. I don't really know what to do.

it doesn't sound like you're going to get perfectly bonded bunnies in the time you have them. same sex couples are not as easy to bond in most cases... Meadow was top bun from the beginning and her nipping of Max made him so scared of her. he wanted nothing to do with her, but the difference is that he did not become aggressive like it seems Benny is, he'd just turn tail and run away. there's only room for one dominant bun so that needs to get figured out. have you done forced cuddling in a litterbox? or stressing (washing machine or car rides?) does your friend live close enough that you could go over there and help her with bonding once she gets back?

It seems like Benny doesn't like to get cornered by another bun. If you can handle them both, I'd put them both into a large litter pan or box top, squish them side by side and then pet them continuously on their foreheads for about a minute. Then take your hands away and see what happens. If they do nothing for about 15 seconds, begin petting them again.

I think if a human puts Theo next to Benny, he may not be as scared.

Sometimes we do the same method that markus recommended above when introducing bunnies. Its a good idea because it helps them get into close quarters without feeling scared because they are both being petted and comforted.