Review on 🐠 Adjustable HITOP Submersible Aquarium Heater: 100W/200W/300W/400W/500W, Suitable for Large Fish Tanks up to 150 Gallons, Includes Sturdy Protective Cover and Thermometer for Optimal Performance by Susan Cox

Wrong for my tank. Mine may have been a failure and I understand that, but the fact that most fish need these things to stay alive is why I would return rather than buy it back. That's very bad because I like the way he looks. Others may have better luck, but keep an eye on your tank once installed. I followed the instructions for the letter T. My fish is subtropical so I haven't lost anything, but tropical fish can be a problem. My tank warmed up to 69 degrees. I prefer to keep about 73. For reference I have 55 gallons. This performance should be fine for 50 and up. I don't like giving bad reviews but for some fish it's a matter of life and death and as such I don't recommend it.