Review on Tetra HT Submersible Aquarium Heater: Efficiently Regulate Temperature with Electronic Thermostat by Dominic Maxwell

I bought 2 of these for my betta tanks, they are both about 5 gallons, the fish always seemed lethargic and lay on the bottom of the tank. I read that they like lukewarm water so I bought them after checking prices at my local pet store. The same at Meijer cost twice as much which made me worry if it would be decent. I plugged both of course into each tank, attached the suction cups, there was nothing to adjust at all, the red light came on and said it was working, after about an hour it turned green meaning it had reached the right temperature, i felt water, and it wasn't very warm, but slightly warmer than room temperature. But before that it felt pretty chilly, almost cold. In less than an hour, both fish were swimming all over the place. That was 4 days ago and while it's still early I have to say it was a great purchase. The fish continue to seem happier, more active, eating better and can't believe how much of a difference this has made. So far, so good. I love my fish idiot I know but bettas are so unique and have personality I'm pretty sure lol! I feel like a much better fish owner after getting these heaters and making the fish more comfortable and I swear their colors appear brighter, maybe a side effect? It's a great value, it works as advertised and automatically regulates the water temperature. I have no complaints about this product.