Right. Try doing a substantial water change, 40-50% (keeping water chemistry the same, naturally) but lowering the water temperature by a couple degrees C. This often stimulates coldwater/subtropical fish.
Stop feeding for a few days. Don't offer anything. NOTHING at all. After 4-5 days, offer something very tasty like an earthworm, and then see what happens.
Cheers, Neale
PS. Your menu sounds pretty good with the vitamins included, but shrimps and herring aren't the best foods (high in thiaminase) and I'd lean more towards earthworms, cockles and tilapia fillet (which are all thiaminase-free).
its about a foot and five inches chemistry is good and i feed it these balls thats a mix of shrimp vegi herring vitamins and i feed him
nonseasoned cooked shrimp ive had it for about 2 years i think i rescued it when it was about a inch and a half