The Marina Compact Heaters are compact, submersible heaters for use
in indoor aquariums. It is designed to reach and maintain the set
temperature of 78 degrees Fahrenheit, without any adjustments. The
exterior is made of a tough polymer so that it will not crack or break
like traditional glass sleeve heaters. These heaters is ideal for aquariums
up to 6.6 gallons and can be used in fresh and saltwater tanks.