Josh's Cadual Fin! HELP!

[Neil D]

Ok so this morning I woke up and checked on my two guys. Max (CT) was fine, but when I looked over at Josh (DeT) His cadual was split nearly in two!!! So I snapped some pics and am now looking for treatment advise.

Housing
What size is your tank? Divided 10G
What temperature is your tank? 82*F
Does your tank have a filter? Yes
Does your tank have an air stone or other type of aeration? No
Is your tank heated? Yes
What tank mates does your betta fish live with? Divided, so one other on the other side of the divider.

Food
What type of food do you feed your betta fish? TetraColor Pellets and frozen Bloodworms
How often do you feed your betta fish? 2 Pellets in the morning and Frozen BW at night, or just 2 pellets again at night.

Maintenance
How often do you perform a water change? weekly
What percentage of the water do you change when you perform a water change? 25-50%
What type of additives do you add to the water when you perform a water change? Top Fin water conditioner

Water Parameters:
Have you tested your water? If so, what are the following parameters?

Ammonia: 0
Nitrite: 0
Nitrate: 0
pH: approx 7.8
Hardness:
Alkalinity: Normal

Symptoms and Treatment
How has your betta fish's appearance changed? Two Large splits in his cadual fin
How has your betta fish's behavior changed? Nothing
When did you start noticing the symptoms? Today Morning around 7:00 AM
Have you started treating your fish? If so, how? No
Does your fish have any history of being ill? Ever since he got nipped by tetras 3 months ago, his fins have never returned to full size
How old is your fish (approximately)? Probably a yr at the LFS then 3 months in my care

Pictures:

[Luimeril]

someone's been a naughty fish, and has been biting his tail. bad Josh!

it's nothing to freak out over. :3 just keep his tank as clean as you can. can he seen the other betta at all? he might be stressed, and has resorted to tail biting to relive it. it's a pretty common thing in HMs and deltas(out of two i've had, BOTH tail bite. i'm trying to break my remaining one, Ichi, of it, because he has the prettiest tail ever!). try to find out if he does it because of stress, or boredom. best way to do that, is to totally rearrange his tank decorations. if he still does it, he may be able to see his neighbor, and it's stressing him out. x:

[fishman12]

It might have never fully healed from the tetras and just got ripped from a small amount of pressure.

[Neil D]

No black really. He can see his neighbor, but they don't really care about each other too much. They do flare, but still....I'm going to put the solid divider in, but there won't be any water flow from side to side, only the warmth will be the same. Before I do that, I'll treat him with AQ salt, and by Wednesday, his new decoration will be dry from the AQ silicone, and I'll put it and Josh back in, maybe he'll be better

[fightergirl2710]

Definitely tail nomming Neil!

[Luimeril]

because they dont' mind each other, doesn't mean the other doesn't stress him out. Ichi never bit his fins till he saw Zidane. they never flare, but he still ripped his tail to shreds. D:

[Neil D]

Kk I'm gonna put him in a qt container with AQ salt. Thanks for the help

[fishman12]

You're welcome!

[Neil D]

WTH?!? I lost the solid divider insert I made! I may be going to michaels today, so what material would work the best? Some sort of mesh canvas thing?

[fishman12]

Mesh works but you might have to replace it after time because of wear and tear.