What is your experience with the growth rate of an oscar fish, what kind of diet did you have them on for this growth rate. I recently got back into Oscar fish and what amazes me is I kept 4 of them in a 10 gallon tank for a few semesters in college. I didn't know back then that they can grow so quickly. I have a 50 gallon now and I am going to get a 150 - 200 when the time comes, use the 50 gallon to quarantine.