Betta, need help

Question
QUESTION: Hi,I have a beta that I have had for about five months now and he has always been in a beta fish tank by himself.Recently I got a 10 gallon aquarium and i got like ten fish and three females I put them together in the aquarium and they seemed fine.they have been there for about a week and just today I noticed that my male beta and one female beta were badly beaten the female not as much but the male yes. At that moment I went to get a seprate tank and put some water in and some aquarium salt in it and put him inside, I also put an oxygen pump in his tank. I also seperated the female in a separate tank she seems fine just resting. But my male beta Mojo seems to be on the brink of death and I am doing everything in my power to keep him alive.Can you give me any suggestions on what to do? Also why did my other fish attack him and the female? They are all tropical fish. Also should i separate the other two female betas? Please hurry and answer. Thank You.
ANSWER: Hi Jack;

Just keep Mojo in as warm a place as you can and change his water daily until he starts to heal. he is in shock right now and needs quiet time to recover. Bettas are very resilient so hopefully he will be okay. Use aquarium salt and Melafix for healing the wounds on both fish and helping to avoid infection.

Not all tropical fish can live with bettas. If they are barbs or other fin-nipping varieties, they will go after the long beautiful fins. Sometimes there will be a male betta that has short fins too. They look like females. They can be faster than the long-finned varieties and can really mess up your other male. If the other females are okay, don't move them. Can you tell me what the other fish are? They may be a fish that will get increasingly more aggressive and grow too big for the tank. There are many, many sizes and types of tropical fish. They definately don't all get along and many are not suitable for 10 gallon tanks. It would be good for you to know what to expect before something else happens.

Let me know as soon as you can...

At Your Service;
Chris Robbins

---------- FOLLOW-UP ----------

QUESTION: Hi,thanks for the information. I got the Melafix for Mojo and when I put it in he seemed to swim around a bit,so I am happy with his health at this moment. How do I get him to eat because he never go up to the top to get food but he does try to eat one or two of the betta bits when I give it to him. Should I be worried about his eating habits at this moment? I also went out to buy a 2.5 gallon tank for the female bettas. I am going to put three females in that tank is that okay? I put the Melafix in Mojo's tank and I have the oxygen pump inside to. When I put the medicine in the bubbles from the oxygen pump make the medicine bubble on the surface of the water. Should I take out the oxygen pump from the water when I give him the medicine or do I keep it in there? I also got you the names of the fish in the aquarium, I have two Black Mollys, four Red Wag Platys, and Four Black Skirt Tetras. Like you said I think the Tetras are the problem  because they bite fins I think, so it was my fault for not reading the label of the fish and endangering my bettas. So if you have anymore suggestions please write back to me. I appreciate all your help thanks. Write back soon.

Sincerely,
Jack and Mojo

Answer
Hi Jack and Mojo;

I'm so glad Mojo is feeling better. It's okay if he doesn't eat much right now. Just remove right away what he doesn't eat. He will not be feeling his best until he starts to heal. Keep his tank really clean. It's perfectly fine that the medicine makes more bubbles appear. Don't worry about it unless there is no place for him to get a mouthful of air. Bettas don't need oxygenated water anyway so you could remove it completely if it causes problems.

The 2.5 will not be big enough for all three female bettas. It's really barely big enough for just one betta really. The general rule of thumb is one inch of fish for every gallon. You measure the bodies without the tail and bettas get almost exactly 2.5 inches long as adults.

The black skirts are probably the culprits. they don't belong in a tank that small, especially as fin nippers. They need a lot more swimming space. Their potential size is almost 3 inches.

Your little ten gallon will be even a bit overstocked with just the mollies and the platies. They will each grow to 3 inches or so and if they have babies it will get even more crowded in there.

Mojo, get better soon....

At Your Service;
Chris Robbins