I have a yellow tang & I'm starting too see around the base of the left fin it's very reddish... PLEASE, What could it be & why it's there ,is it going too get worse???????????Dee
Honestly, you've had a lot of questions and I know you called me sarcastic, but I think you jumped into this hobby way too fast. Everyone is willing to help, but I'm wondering how much research you're doing on your own. At any rate, my thought is to get the tang into QT and pay very close attention to keeping ammonia and nitrite at zero.
I would lean towards agreeing with Mandy...We ideally need water params, photo's...there are quite a few things i suppose it could be, however, i would not like to second guess on something like this....