So my female betta Delta who was living in my sorority had been really gloomy. When she was living in the sorority her fins were torn pretty badly (I think it's because I have a lot of plastic plants), all she would do was lay on the floating plastic plant, stress stripes, and usually she wouldn't eat.
I moved her to my 2.5g tank with a heater (kept at 72) about 3 or 4 weeks ago. I was hoping with some salt & heat she'd be feeling better in no time. NOPE. Her fins are healed a little bit, but she has stress stripes still and she won't eat. All she does is stay next to the heater or lay under the live plant. She'll start to move towards food, then stop.
I have nooooo clue what is wrong with her. She used to be a little feisty fish & now she won't even eat.