Is this fin rot or he a tail biter?

[SQUIRT1216]

Hi, I am new to this forum. I recently became a betta slut and currently own 3 male bettas

The red one is the first one i got, his name is Squirt (my user name), the blue one is Mr.Pimp

The lavender one is Sushi.


Anyways, I digressed. Mr. Sushi tail is tear up so is this fin rot, tail biter or bad water condition? I dont think it is the last reason because i tested the water (he live in a divided 10 gallons with Squirt) and how to fix this problem?

[callistra]

He may also be a biter, but see how it's turning brown? That's rot.

What are the ammonia, nitrite and nitrate levels of your aquarium? Strips are not accurate so make sure you use a drops test kit.

[SQUIRT1216]

I just bought it yesterday so probably it already had it at the store. Do you think it will heal on its own or does it require special treatment?

[callistra]

I would quarantine him and treat him with aquarium salt and stress coat for a week or two, but it should clear up. This talks about how to treat fin rot with salt: http://www.bettafish.com/showthread.php?t=73332