Review on Hydor Slim Heater for Bettas: Optimized for Bowls and Aquariums by Madhu Plexico

I installed a 5.5 gallon betta tank on my desk in my office and since the tank was smaller I wanted to try to hide the heater as much as possible. I chose the Hydor as it was fully submersible and was told the cold heater would need to be buried under the substrate. The heater arrived and everything looked fine at the first inspection. The heating pad was nice, wide and even supple. The cable was long and came with a cable guide and suction cup to make routing the cable easier. Once in place, the heater looked exactly how I wanted it, invisible except for a cable running up the sides of the tank. When it was in the tank everything was fine at first and the heater got the tank up to a decent temperature like 78 or 80. Over the course of a few weeks and the change of seasons I noticed that the temperature fluctuated between 68 and 84 degrees. I won't blame the heater for the hesitation. The heater did exactly what it was advertised to do and did it well. The large fluctuations in air temperature in our office are exclusively related to the ambient temperature. During the winter months the ambient temperature is very high which causes the tank to heat up as the heater is always on. Now that it's summer, the A/C is on and it's very cold, the 15w heater just doesn't have enough power to heat the tank. small tanks. Cons: This product doesn't have many cons, but it seems that the useful application of this heater is very limited.