50W Pro Heater, Beautiful EcoFriendly Moss Preset 2x Size Heaters50w Pro PRO 24050 Aquarium Actively Light Curbs AQUEON 50 Them 50W 10 Universal.., By Aqueon Ship from US - Walmart.com
Amazon.com: HITOP 25W 50W 100W 200W 300W Adjustable Aquarium Heater, Submersible Fish Tank Heater Thermostat with Suction Cup (50W) : Pet Supplies
Amazon.com: Aqueon Submersible Aquarium Heater, 50 Watts, Up to 20 Gallons : Pet Supplies
Amazon.com: HITOP 25W 50W 100W 200W 300W Adjustable Aquarium Heater, Submersible Fish Tank Heater Thermostat with Suction Cup (50W) : Pet Supplies