Review on 🐠 Submersible 100W Aquarium Fish Tank Heater - Mini Fish Heater with Built-in Thermometer, Dual Displays & Remote Controller for 5-20 Gallon Tanks by Kyle Beaner

I bought it in January 2021. It is now March 2021 and it no longer works. Deviation by 10 degrees! Thank goodness it wasn't a mistake the other way or it would have killed my poor fish! Unfortunately he started doing it just before the return window and I had a hard time contacting the seller to redeem the 1 year warranty. Very disappointed.