He has black spot disease, which is a parasite. It is also known as "black ick". This variety of parasite, however, is not the same as ick, nor is it as deadly.
You need to treat with daily formalin bathes at threaputic levels. Keeping the fish in the bathe for about 30 mins. Do you have a separate hospital tank? What is this fish's diet and how long have you had him?