All aquarium heaters suck. You just need to choose one that sucks the least, and use more than one controller. I dont like any glass models, because they can break or crack and fry all your fish. I use a finnex heater connected to a finnex controller, and then connected to my Apex. Sounds like a lot, but it’s the best way to monitor the heater. The Apex is so much better at temp control than any heater on the market. The aquarium companies need to come up with an industrial heater that is more reliable and SAFE. We spend thousands on lights, pumps, fish and corals, but we’re still using the same crappy heaters that have been around since I was a kid. Good luck.