Aquarium Masters Temp-Tec 100 Watt Professional Aquarium Glass Submersible Heater for Freshwater & Saltwater Aquariums, aquaculture, terrariums & hydroponic Systems! The Professional Aquarium Glass Submersible Heater, 100 Watt, provides accurate thermal control for freshwater & saltwater aquariums, aquaculture, terrariums & hydroponic systems! Heats 25 gallon aquariums to 35 gallon aquariums. Quartz Silica Tube - Maximum strength Quartz Silica Tube is shatter resistant & more durable than conventional glass heaters. A gravel guard tube cap & advanced mounting bracket is included. Mounts both vertical or horizontal positions. Active Indicator - The Blue On/Off LED indicator & temp setting is easily viewed from multiple angles Submersible - 100 Watt heater is completely submersible in both freshwater and marine aquariums Active Indicator - The Blue On/Off LED indicator & temp setting is easily viewed from multiple angles Safe & Reliable - Quality construction & advanced design for safe reliable operation. Accurate thermal control via "Easy Set" thermostat for precise adjustments. Other items to consider are: aquarium filters, hydroponic filters, carbon pads, nitrate pads, filter pads, air pumps, and round air stones