What is going on with his fin?

[caitic10]

Ugh...I hate posting here. :(

What size is your tank? 5 gallon divided, so 2.5 gallons
What temperature is your tank? I need to find my thermoniter...
Does your tank have a filter? Nope
Does your tank have an air stone or other type of aeration? nope
Is your tank heated? No, but the temperature stays steady and suitable
What tank mates does your betta fish live with? He is in a divided tank and can see the other male clearly

Food
What type of food do you feed your betta fish? Omega One betta pellets
How often do you feed your betta fish? 2 pellets in the morning, 2 in the afternoon, fast one day a week

Maintenance
How often do you perform a water change? Usually three times a week, but this week only twice so far.
What percentage of the water do you change when you perform a water change? 50%, 50% then 100%
What type of additives do you add to the water when you perform a water change? Water Conditioner

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

Ammonia:
Nitrite:
Nitrate:
pH:
Hardness:
Alkalinity:

Symptoms and Treatment
How has your betta fish's appearance changed? His anal fin is torn and ragged. No black lining, just little white specks along his anal fin.
How has your betta fish's behavior changed? No...
When did you start noticing the symptoms? This morning, just now
Have you started treating your fish? If so, how? I am going to separate him and put him in a litttle cup
Does your fish have any history of being ill? No
How old is your fish (approximately)? Just got him a few weeks ago

I will upload pictures soon...

[dramaqueen]

I'm sorry this is late but can you post a pic of him?