Most aquarium fish come from warm waters and need to be above room temperature. Aquarium heaters are inexpensive and keep temperatures stable no matter what it's like outside - vital since fish don't produce their own body heat (and hate fluctuating conditions).
Our fish tank heaters come in two basic styles: fully submersible heaters, and heaters that go in your canister filter, power filter or sump. Either will get the job done, so decide based on the aesthetic you want and your budget. Browse brands, styles or scroll down for our complete selection. And make sure you have a thermometer!