marineland Precision Submersible Heater, for Freshwater or Saltwater Aquariums

I replaced my other heater because I couldn't tell if it was working or not. This filter has a built-in thermometer and a light indicating that it is working. Plus it has a lifetime warranty

I received the item fast and I am using the Marineland one right now and so far it is working great, but I still haven't received my full refund for the Christmas gift cards that I ordered from Walmart and never received as of yet.

The heater is working perfectly for my 40 gallon tank.

This is great it really warm up the water

Love that it has a temperature gauge on it. Easy to use.

Very nice. I really like that you can set an exact temperature for your fish tank.

I needed a heater in a hurry for my cow's Farm trough. I could get this shipped quickly. It's working fine until I get her permanent heater installed. It kept her trough thawed in 5° weather.

This heater works fine so far, after about a week of use. One thing I don't like is that it uses only suction cups to keep it in place from falling into the water; I imagine the rubber getting brittle after some time, slipping from the glass, and the heater being dunked. Maybe the rubber used nowadays is a newer type that stays flexible permanently. Even so, does the rubber-to-glass seal never get compromised? It would seem more secure if a simple plastic hook were attached to it to hold it in its spot. Other than that, it maintains an even temperature once I set it, and its design and style blend well with the aquarium.

It keeps my aquarium at the right temp. If you want to see the built in thermometer you have to use a flashlight. I use a separate thermometer.

I didn't get to use this for more than a couple hours it filled up with water and began overheating the tank.