Sunfish have been successfully kept in aquaria and even bred. Largemouth bass can be kept in very large tanks. Go to any Bass Pro Shop and look at the tank. There are various species of gar in FL & GA.I really don't think those type of fish are suitable for such a small tank. Not really aquarium fish at all.
Tony you got that right. Some people carry this to insanity and beyond though. Go check out Monster Fishkeepers Forum. Me; I'm not interested in the giant mess, expense and extra work that goes into keeping that kind of stuff. I'd rather just go look at it in the wild.Guess you will have to FEED these fish large quantities of FOOD....lol