I have one male crowntail betta in an aquarium shaped like a lava lamp. It was one of those "all in one" kits with the tank, stones, and air stone/pump. He seems ok but I read that bettas actually prefer warmer water. As this tank didn't come with a heater, like most betta tanks, any suggestions how to warm it? A traditional over the back heater isn't going to work, and I have cats so it's mandatory the lid stay on top. This is the actual one I bought:
Since the top is solid, a top heater isn't going to work very well either. So I'm stuck on ideas.
Like I said, he does seem fine. He eats, he swims, he puffs up, he has nice color, etc. He did have a small "bubble" between his front fins which I was advised was from too much air. Since bettas go to the surface to breathe, I removed the air stone, the bubbles went away, and he's been fine ever since.
I would like to keep this tank but I also want to provide the right water conditions for my fish. Any suggestions appreciated.