Review on Efficient Submersible Heater for Marina Betta Fish Tank Aquarium, 1.5 Gallons by Lisa Rice

I couldn't find a heater for small tanks without most reviews being negative. Since I really needed some, I took a chance and bought 1 for each of my 1.3 gallon betta tanks. I've had them in tanks for about 2 weeks and they work as expected. As some reviews say, it is true that this heater stays on all the time when plugged in and you have to take the room temperature into account. Now that it has gotten cooler, the temperature in the aquariums is stable at 82 degrees and the fish are happy. As the weather warms up, I'll adjust how long they stay online. I would like to mention that for the first few days the temp of one of the tanks was a bit higher so I unplugged/plugged in the heater as needed but this seems to have acclimated and hasn't risen above 82 since even at the location of this one special tanks because the other one didn't have this problem. Both heaters remain well aspirated and small enough to leave plenty of room for fish, live plants and a small den in each tank. In general, they work exactly as I need them to. While I would like the temperature to be adjustable, I don't think we can have everything.