Hello! I was hoping to get some suggestions as I'd like a bright but peaceful center fish for my 20 gal long (As well as some small tetras if possible). My tank looks pretty empty right now in mid and upper regions! Here are the current fish in the tank. Cory cats are not subject to change. x10 Guppies x3 Agassiz's Corydoras x10 Bladder Snails I have a Top Fin Power Filter 20 and have 4 plants in the aquarium as well as other hidey spots for the Cory Cats. Any help is appreciated!