Aquaking heater to regulate the temperature of the water in the nutrient solution tank. It is submersible, it can be both horizontally and vertically. We use the heater because a cold water supply can put stress on the plant, slowing down its metabolism. If the water is hotter than it touches, it could lead to slow growth and oxygen starvation, and could even lead to a pathogen infection. The ideal temperature oscillates between 18 and 24 ºC. For good heater performance and durability, unplug it 15 minutes before changing the nutrient solution. Features of the Aquaking HE-200 Wide range precision electronic thermostat Fully electronic thermostat, without mechanical elements susceptible to failure Indication of the current temperature of the water in the tank Clear indication of the set temperature Specifications of Aquaking Water heater 200W (HE-200) Brand: Aquaking Model: HE-200 Precision Temperature ºC: 22-34 Power 200W Suitable for 200 liters of water Dimensions (width x depth x height): 32x34x3453mm Temperature regulation Fully electronic