Marineland Shatterproof Mini Heater Aquarium Heaters at Pet Mountain

On March 13, 2012:
I bought two of these heaters for each of my Betta tanks. The box states that they are pre-set for 78 degrees, but I came home from work and found two dead Betta fish that were cooked since the water temperature rose to 100 degrees.

On April 11, 2010:
The heater seems to be working fine, but I've only had it for two weeks. Unfortunately, I misunderstood what submersible meant. I thought I could put it entirely in, under the gravel. It can in fact only go in on the side of the tank. My only other disappointment is that it is longer than I thought. Some dimensions on the website would be helpful.

On October 25, 2009:
The good things about this heater are that it is compact, easy to hide and made out of shatter proof plastic. However at 10W it is a bit underpowered. I have it in a 3 gallon eclipse and it only keeps the temp at 78F when the temp. in the house is at least 70F. If the ambient temperature in your room/house drops below that like most of ours do in winter, the temp in your tank will drop to 75F or even lower. Below 76F is not good for tropical fish. It seems like this heater can only raise the temp. about 8F above ambient tops. If you keep this in a 1-2 gallon bowl, it will also struggle because you'll lose heat from the bowl being open at the top. I would only recommend this if your room temperature never goes below like 70-68F otherwise your fish will be a bit cold.

On January 4, 2008:
I own 8 of these Marineland 10 watt heaters and they are incredible for small tanks and bowls. Bettas simply do not do well in cooler water and all mine are active from sun up until sun down now that I have these heaters in each of their 2 gallon tanks. No more "hanging" at the surface or sulking on the bottom to keep warm I have a stick on thermometer on each tank and the heaters stay consistant at their preset temp no matter what the room temp is. I love the small size, the black housing which is unobtrusive and the price at Pet Mountain blows the competition away. Thank you for offering such a superior product at a great price