Amazon.com: auomii Mini Submersible Aquarium Heater, 25/50/100/150/200/300 Watts Adjustable Fish Tank Heater, Built-in Thermometer, External Temperature Controller, Smart Memory, Used for 1-60 Gallons (50 Watts) : Pet Supplies
Aqueon Pro 100 Submersible Aquarium Heater | Petco
Aquarium Heaters & Submersible Fish Tank Heaters | Petco