I have been taking care of my Betta fish for past two years and she has been super happy and was relatively active. Recently though she has lost her appetite all together and hasn’t eaten in the past 4 days. She has had swim bladder disease once 7 months ago but it was cured and she went back to normal. I check her water for nitrates, nitrites, ammonia and ph levels every month and everything is always at 0ppm. I feed her bloodworms, pellets or flakes and only a couple a day. She used to eat 3 pellets a day but now won’t even have one. I tried changing food but it’s not helping. She seems uninterested in anything and usually lies at the bottom of the tank. I look for any visible signs of disease but I don’t see nothing on her except some discoloration on her face. She doesn’t have the cotton disease or fungus or anything that I can point out. When she needs to swim up for air she goes without issues. I don’t see any other visible signs and cannot find out what’s wrong with her. She doesn’t have fin rot, they look normal. Her tank has a live plant,I used seachem substrate below her blue rocks. I added a drift wood to keep her ph steady. I sometimes add aquarium salt to as instructed with her water changes and I always de chlorine her water with water treatments and let water settle before I add it to her tank. She also has a heater on at all times with constant temperature. She is in a 5 gallon fluval spec tank fully cycled. I tried to explain as much as I could, can anyone please take a look at the picture and please let me know what’s wrong with her? She used to be all happy when I came home but now she seems sad. I took a picture of the tank just now, I’m making a water change so the water is not topped off. I wanted to point that out before I get criticized, I also moved her from my desk near a window few meters away to the hallway thinking she might get stressed out due to light. She wasn’t fully exposed to sunlight I kept her at the corner of my room but that room has a lot of sunshine. Please help me if you can, I tried explaining everything I could. She can swim properly but I find she sometimes hits the wall somehow. I don’t know what to make of it.