I have had this tang yellow tang for 4 months now and all the sudden he stopped eating. All water parameters are in check and all other fish are fine. I feed LRS herbivore blend and nori and all was good until now. I also just got some Mastic to try and he didn’t even attempt to eat it. Sal = 1.025 Alk 8.8 ph 8.15 nitrate .5 Calc 480 mag 1290 everything else is zero. Oh I also tried dipping the Nori in garlic with no success. He also tend to be shy and hide a lot. He also swims nose down and kind of goofy compared to before.