The Marina C 25 is a 25 watt compact, submersible heater for
use in indoor aquariums. Without any adjustments needed, it is designed to
reach and maintain the set temperature of 26ºC (78ºF). The exterior is made of
a tough polymer so that it will not crack or break like traditional glass sleeve
heaters. The heater is ideal for aquariums up to 6.6 gallons (25 L) and can be used in fresh and saltwater tanks.
Good product for the money by Hobo Joe from Wisconsin10/22/2012
Very happy with it. Own 2 now, one for a 5-gallon eclipse corner tank and one for a 6 gallon eclipse. Keeps both at constant 77 degrees. There is no temp control, and it does keep the tanks slightly cooler than advertised (package says pre-set at 79 degrees). However, unlike other small heaters, it does turn off when temp is reached and on when needed. MUCH better than my previous 15watt constantly on heater...it was smaller, but kept the tank way too hot.