Water Heater for Fish Tank 50 Watts is a compact submersible electric heater designed to maintain stable and precise water temperatures in small fish tanks, aquariums and aquaculture containers. With adjustable temperature control, built-in thermostat and automatic safety shut-off, this 50 watt heater is the ideal affordable temperature management solution for small tanks of up to 50 litres and is perfect for Nigerian aquarium hobbyists, fish breeders and small scale aquaculture operators.