The Ready-Set Aquarium Heater’s silicon crystals effectively distribute and transfer heat while the design’s shatter resistant quartz glass provides durability for freshwater and saltwater use. Heats up to 55 gallons.
Heater holds 78 degrees in my 29 gal aquariums and has led internal red and green lights to indicate heating and stand by. It’s heavy and stays where I put it. No adjustments but it is preset to temperature I prefer. Very reasonable price.