Review on 🐠 Zoo Med BettaTherm: Powerful 7.5 Watt Submersible Betta Bowl Heater for Optimal Comfort by Victoria Smith

I bought this for a 1 gallon battle tank. I didn't put it under the sand straight into the water before putting the fish in because I wanted to see if it even worked. And of course it didn't warm my water one degree! I do not understand it. You are not working. Since then I have a bigger tank and a better heater. Smaller 1 to 10 gallon heaters claim to work, but they don't seem to work. And actually seeing your rooster swimming in a large aquarium is sooooo worth the money I promise. At least a 3.5 gallon tank. But now I have a 5.5 gallon betta that looks so happy and healthy. Not to mention that it's easier to ride a bike.