My Oscar is about five, I talked about him in my introduction, he was in a 55 gallon tank and last week we moved him to a 125 gallon tank. The Oscar is about 10 or 11 inches. A few days later he looked like he was in a fight. It looked like scales were missing and one eye was covered in what I described as white plaque or cotton ans the other eye had a little white spot. I bought Melofix, for four days I used it as directed but now he looks worst. I have a filter by Aqueon Quiet Flow 75, water temp 78, 0 amonia, 0 nitrate, ph is over 7.6.