Ahhhhhh! It's been a hell of a night. I have a 10 gal sorority tank with six girlies that has been running beautifully for the past 5 months. There are a ton of hideyholes and plants for them to stake their territory but they all choose to 'school' together in the front of the tank, begging for food (piggies that they are). It's been hunky dory until last Monday when I come home from a concert to find Morgana, my gorgeous green and black HM, lying motionless at the bottom of the tank. She was still alive, but barely. I immediately put her into her own bowl which I medicated with Bettafix and changed 80% everyday. She was looking better and her wounds were healing but she lost the fight on Friday

There was no visible aggression in the tank at any point through this, however I noticed that my little CT had a patch of scales missing on her belly. Today I came home to find Iris, my blue and yellow girl, listless and in hiding. It looked like she might have some sort of mouth fungus going on so I QTed her and dosed her once more with Betafix. Upon close inspection it looks like the fungus could also be battle wounds. I then did my normal weekly 30% water change, placing the remaining 4 bettas in cups so I could scrape down the algea on the side of the tank. When I was done and put them back in, my CT started picking a fight with my blue and red Maxine. Before it got too ugly I moved the CT to my brother's 5G (currently housing 2 zebra danios). Next thing I know another betta, my white one, is chasing Maxine around the tank so I also have her in a little 3G for the night. So right now I only have 2 girls in the 10G, both are very shy and they seem to be doing alright for now.

So, what went wrong? I'm so sad that this is happening, I really enjoy watching them swim together. My mother very kindly went out and rescued another betta from Petsmart that I have in QT at the moment, so I currently have 6 bettas in four seperate tanks (not including my male). Is there anything that could be done about it? If I took down my tank completely and rearranged it, would they sort out the order again and continue to live peacefully? My mom has a beautiful 46G peaceful community that already has 7 females in it. If I absolutely can't house my girls together in the 10G, do you think I could rehome them my mom's tank successfully? Of course I will do what's necessary to make sure my girlies have adequate living space and safe accomodations, but I would really like to avoid having six little 3G tanks in my room (I already have a male betta and a large goldfish in there, not much room for anything else!). All suggestions and advice is greatly appreciated, thank you.

you'd have to figure out who started the row that triggered to whole thing.
might be the first one to die, everyone else ganged up on her for her violence or something like that... that would mean the rest were fighting for dominance.
You might try to completely redecorate the tank... ie. moving EVERYTHING around... and reintroduce the fish...
But keep an eye on them as this may or may not work. Also, lowering the temp to around 80 degrees might help too...
slows them down a bit until they establish hierarchy again.

This is my take...
There was a dominance fight, and Morgana lost.
I'll bet money she was a high ranking fish.
With her loss, and subsequent removal, the whole hierarchy was in shambles, and the tank began to fight to establish the new rank system.
I think that perhaps the CT won Alpha position, and was asserting her rank when you saw her "picking a fight"
You did, IMO the worst thing you could have done, which was remove her.
Obviously Maxine is an omega, or lower ranking fish, because as soon as the CT was removed, and because she had not established herself long enough for peace to settle over the tank.. The next lower fish saw a chance to slip into the top spot, and she too took the opportunity to assert her dominance...
Usually, once the tank rank has been established, you can remove one of the inhabitants for up to a week.. I have done so for up to 2 weeks, and returned her with little fuss to her sorority, and usually she is able to slip back into her old rank seamlessly.
However, this is with long established tanks.
But you tank doesn't have an established rank anymore.

As hard as it may sound, you may have to completely rearrange the tank, reintroduce them, and let them fight it out.
If things are getting a little too hairy, then intervene, but I would not pull any fish while in the middle of the attempt to reestablish your sorority.
If you have any idea of what the previous ranking was.. put the omega fish in first, and work up the scale.
I know that this is going to be hard, because of the turmoil your tank was in before you pulled them, but putting the lower ranking fish in first will help to alleviate that. But because you will be going into this is a first time set up, there is going to be a lot of scratching, kicking, and hair pulling until they figure out who is the new boss, and who is second, and so on.
Also, I want to point out that at 80 degrees they are pretty active as that is an ideal temp for them.
If you could drop them to say.. 76. That would indeed help to slow them down, and lessen the damage to each other.

LaBella.. about the temp... you're right... I keep mine at 84 most of the time... so for me 80 is enough to mellow them out when they are getting a little nuts

Just until they get used to it, lol.
My tanks are usually from 79-82.. without added heat. People say how can you live without AC... I look at them and say...
Then I couldn't live with my fish, du-uh. lol.

The funny thing about it is that Morgana was NOT a particulary high ranking fish (4th out of 6), in fact the CT is above her in the heirarchy(2nd out of 6). Of course it is entirely possible that Morgana was the aggressor, however I was out of town for the night and came home to a badly mauled girl in the morning. I felt so bad that I wasn't there, she could've lain there for almost 24 hours for all I know. That's why I took the pains to remove the CT when she started beating up on Maxine, as I was leaving for the night again and couldn't keep an eye on them (ditto with the great White Alpha).

As it stands, I'm still not sure if the mess on Iris' mouth is a fungus or a battle wound so I'm keeping her in QT until that's cleared up. I guess I'm just gonna have to deal with all the separate tanks until I can pull everything out, rearrange and then reintroduce EVERYONE together.

If it continues to not work, would adding them to a well furnished (lots of space, lots of holes) 46G established community be an option? My mother hasn't had any pervasive aggression problems over the past year and she's up to 7 bettas right now. Maybe adding one or two at a time slowly? I just want my girlies to be happy.

Thanks so much for all the advice, especially about lowering the temperature. I don't know if my heart could handle WW3 breaking out in my 10G.