I recently purchased an established 90 gal salwater tank with abt 200 lbs of live rock and sand. It is came with 7 fish, I have had the tank for about 3 months and have added 3 additional fish since. The list of the fish is in my profile the first three on the list are the fish I purchased. The question is can I add any more fish without over crowding and if so any advice on which species.