The quartz glass adjustable heater maintains an even temperature level in aquariums. Choose the right size of the heater, depending on the size of the aquarium. The adjustable heater is high-quality, easy to install, and can be used in continuous operation. The activated indicator light lets you control the heating function with ease. The HeatUp adjustable heater is suitable for use in freshwater and saltwater aquariums. It can also be retrofitted with the BioMaster, BioPlus, and FiltoSmart.