Review on Hydor Slim Heater for Bettas: Optimized for Bowls and Aquariums by Cassandra Parkins

I read so many reviews of small heaters it made my head spin so I finally decided to buy two of these for my betta bowls . I had them for about 24 hours and they made my two males very happy. I have two vase type bowls, yes I know they "prefer" more space, but I'm talking about heaters, not betta habitats. They each hold about 1 gallon. I also have river pebbles and bamboo. I thoroughly cleaned the bowls, stones and heaters. Then put a layer of pebbles, a heater and more pebbles on top. I refilled the bowls, added some aquarium salt and put the roosters (Todd Gurley and Dash) back in their bowls. I turned on the heaters and watched in awe for any signs of overheating or stress. Well both my boys are happier than I've ever seen them. The water temperature is around 78 degrees (70 degrees indoors), so it lives up to the advertising, although the bowls are smaller than recommended on the packet. My fish are swimming around, blowing bubbles and eating like devils. I had to increase her feeding schedule due to her increased activity. TG likes to spend time directly over the base of the heater while Dash prefers to sit on the curved bamboo ledge. The heaters fit well and are not very noticeable. I glued the cords behind the bamboo and to the edge. I am very happy with them and to be honest if they only lasted 6 months to a year I would still be happy and would buy a new one. I don't see that as a problem as I'll take them off once it gets warmer and leave them for the summer.