Betta fish white fuzz. **HELP**

Aug 16, 2017
Hi, this is my first time on a forum. Hope I am doing everything right.

So I have a betta fish that I just bought on Saturday-5 days ago. She is a veil tail betta named Finn. She looked perfectly healthy at petsmart when I bought her. Then probably the third day of having her I noticed a little bit of white stringy fuzzy stuff on her spine. I ignored it thinking it was probably just debris from the tank. I go today to check on her, and she now has it on her bottom lip of her mouth, her butt-tail and the tail on her back. She has almost no back tail left, and her butt tail is starting to be eaten away at by this white fuzz. It doesn't look like fin rot at all, her fins look normal other than parts missing from white fuzz. She is eating normally and very eagerly. She is very active, but I noticed today she is darting really fast around the tank. I want to know any info and how to treat it? I think maybe it's fungus?

Tank setup:
2 gallon bowl (pls don't be mad at me)
Filter (carbon cartridge type)
No heater, but water is at a constant 73-74 F
Tetra whisper bubbler
One amazon sword (just picked up yesterday)
50% water change EVERY OTHER DAY. Although about two hours ago I did %75 to see if that helps the fuzz on her.

Any help is appreciated, please help me get my girl better (or should I say betta looool)


New Fish
Oct 9, 2017
2 gallons should be fine because you can keep bettas in quarts. Using gravel should help a lot. DO NOT change more than 30% every week. If it is not long you can still go and check with petsmart what the problem is. But gravel is the best option.