I have been in this hobby for the last 5 years and I have never seen Brown spots on my fish. YesterdaY I noticed a couple really small brown spots on my Blood Parrots head at first I wondered if they where always there but then noticed them on my other Blood Parrot today. the tank has been set up for 4 years and I do 30% water changes twice a week. in the tank there are also a Reticuleted Ray a pair of Emperor Sharks a 12-13" Pleco and an Arowana. Any Ideas what it is and how to treat it?