Best 1 Gallon Fish Tank Heater

Tetra HT Submersible Aquarium Heater With Electronic Thermostat, 50-Watt

HiTauing Aquarium Heater, 50W/100W/200W/300W/500W Submersible Fish Tank Heater with Over-Temperature Protection and Automatic Power-Off When Leaving Water for Saltwater and Freshwater

NICREW Aquarium Heater 200W, Temperature Adjustable Fish Tank Heater with Controller for 30-50 Gallon, Overheat Protection

HiTauing Aquarium Heater, 300W Fish Tank Heater with LED Digital Display & 5 Safety Protection, Submersible Aquarium Heater with 2 Suction Cup and 8.2Ft Cord for 40-75 Gallon Fish Tank.

Fish Tank Aquarium Heater - Adjustable Temperature Submersible Thermostat Heater,25W/50W/100W/150W/200W/300W

NICREW Submersible Aquarium Mini Heater, Small Betta Fish Tank Heater with Electronic Thermostat, 25W

DaToo Mini Aquarium Heater 25W Small Fish Tank Heater 25 Watt with Free Thermometer Sticker, 1 Yr Warranty

Adjustable Mini Aquarium Heater 0.5-40 Gallon Submersible Small Fish Tank Heater Digital Display Thermostat External Temperature Controller 10W/20W/30W/25W/50W/100W/200W

Pawfly Submersible Aquarium Heater 25 W Betta Fish Tank Heater Adjustable Electronic Heating Rod with Thermostat Overheating Protection and Protective Cover for Fish Tanks up to 10 Gallons

Abhirsh Aquarium Heater 50 Watt - Reliable Fish Tank and Immersion Water Heater, Adjustable Temperature Submersible Thermostat Heater for 5-10 Gallon