7.5 g Betta tank So, I moved my male betta from a 5 hex which had limited swimming room to this 7.5 bowfront aquarium I bought. I added a small internal filter with a seeded sponge and gave him some places to explore and some live plants since he was becoming a tail biter. We made a plexiglass lid for it and I've left room at the top for air. I have a nerite snail that used to be with him that I'll add back to the tank if/when I have an algae issues. It's in a bright sunny room, so I don't use a light often, though there is a flourescent desk lamp I can swing over to it when needed. Love this tank.