Review on 🐠 Zacro 100W Submersible Digital Display Mini Fish Tank Heater with Intelligent LED Temperature Display and External Controller, Suitable for 10-20 Gallon Aquariums by Jeff Payne

This heater works very well and has kept the tank temperature within a degree so far. The remote control is a great feature, it's so nice not to put my hands in the tank every time I need to adjust it. But as other reviewers have said, if you have small fish or it is absolutely IMPORTANT, block the space between the suction cups. Within an hour of putting this heater in the tank my betta was trying to wedge itself in between where it could get stuck and burn. I tore off pieces of the moss ball and stuffed it between the heater and the aquarium pane so my betta fish couldn't get in between. In the video I uploaded you can see he tried to do the same thing at the top of the filter but that part isn't close enough to the glass for him to get through. I also blocked him with moss after making the video because I don't really want him resting behind the heater. This is a major design flaw that I am asking manufacturers to correct by inserting something between the suction cups to block access.