Review on Aquarium Submersible Temperature Intelligent Controller by Turbo Jiles

This product was used for a quarantine aquarium. The first day I used the heater the water seemed slightly warm. The next day I saw my fish was getting worse and upon further inspection the water temperature was very cold when I put my hand in the tank. I even felt real heating and it put out a minimal amount of heat, not even enough to heat even a bowl tank, let alone the 3 gallons I quarantined a fish in. My fish later died but was sick before then so don't blame the heater but the water was freezing even after heating it to 90 degrees. I'm not sure if my item was defective but I would not buy from the company again.