Fluval M 150Watt Submersible Fish Heater; The Fluval M 150Watt Submersible Fish Heater is designed to be reliable and durable, perfect for fresh and saltwater tanks. It's designed in Europe and is sleek and compact to fit well in your aquarium. The submersible heater features mirror technology that reflects the tank's colors to enhance the overall appearance of the space. It's an easy and attractive way to keep your finned friends warm and comfy. Quality heater made in Europe with quality components. Sleek and compact design. Submersible heater delivers excellent performance and reliability. Mirror technology reflects the colors of the aquarium to enhance its appearance. For fresh and saltwater tanks.