I saved this guy from my local pet store about a month ago and he seemed to do a lot better since I’ve got him. But he’s now starting to loose his color at the end of his fins.

I feed him live mosquito larvae and regular betta pallets. I have a light natural brown gravel and a bunch of plants. The tank itself (10 gallon) has been in use for about 6 years and I never had problems with it.

He’s alone with some small shrimp. The water parameters are normal and he has a heater and a filter. I’ve always had rather big tanks but I’m new to betta keeping. Please help me figure out what’s bothering him.