Hello, I have 3 red blood parrot fish (2 inches), 1 cichlid severum (2inches), 1 Oscar (3 inches) and 1 chocolate zebra planco. I have a 46 gallon tank, filter canister penguin 200 for 50 gallons, heater at 79 degrees. I would love to add at least 1 more fish. My local pet store has 3 that I am...