Hi! I recently bought a 10 gallon tank and am in the process of moving my old fish into the new tank. After they are all moved, I will have a extremely calm (Has never been seen flaring EVER) male Betta, and small Cory catfish and a Tiger Snail. I was wondering when should I introduce new fish to the tank, and which types?? For the most part, I want what is best for my betta, as he is almost two, and want to help him have a long life. Details about the tank: Kept by a window 75-80 degree temp (with heater) Pretty regualr water changes (around 30-40%) 10 Gallons Running for 2 days (1 day w/out fish) (since 1/1/17) Not a ton of hiding places No real plants (I can get some if needed including moss balls) Male Betta that never flares or shows aggression Cory Catfish that spazzes out hence his name "Spazoid" Extremely lazy tiger snail Thanks! -Devin S.