Aqueon Preset Aquarium Heater, 150-watt

Aquarium heaters are notoriously prone to overheating and need to be inspected and monitored a lot more than you might be doing already. This specific heater thankfully didn't malfunction during the few days I used it, but where the cord connects to the top of the heater, it looks like it isn't equally sealed on both sides like my other 50watt Aqueon heaters. Heaters are not immune to water getting in and shorting them out, so out of caution I am no longer going to use it for the 20 gallon community tank I take care of. However, I moved one of my 50watt Aqueon heaters into a better flow zone (near the air stone instead of under the filter outflow) and it's doing just as good a job if not better as the 100watt when I check different parts of the tank with a thermometer. 77-78 all around, when the room is at 70-71. I would recommend using a less powerful heater in a high flow zone in your tank, all while making sure the room itself is as stable a temperature as possible so the water heater doesn't have to work as hard. And please follow the manual and make sure not too much of the heater top is above the water. Best of luck, and keep an eye on it.