Review on MarineLand Precision Heater: Optimal Temperature Control for Saltwater and Freshwater Aquariums by Helen Love

Replaced a few months ago under lifetime warranty. At that time, the device no longer heated up and the temperature dropped to dangerously low values overnight. When I received the replacement block, I chose it perfectly. The temperature was stable and practically did not fluctuate. Before. a few weeks ago my wife noticed that it had risen by about two degrees. I reset it and so far everything is looking good again. 22:00 today. My wife comes into the bedroom and says we have a lot of dead fish and an aquarium with a temperature of 97 degrees. I have fished over 20 adult mbuna cichlids easily worth several hundred dollars. To tell the truth, I don't care how much the fish costs. They didn't deserve the suffocating, slow death they deserved. I did a water change to lower the temp and removed the heater. Hoping the shock of the 97 change will bounce back to a slightly more normal 82 (I usually run them at 79-80). I left the lids open overnight to allow the temperature to drop gradually. Put in an old heater. But what can you do? Get another useless free replacement. I do not think so. My fish didn't deserve the inhuman death they suffered because of this heater malfunction. Run, look for something else that will be useful for your fish.