Ok, so far I had not had the need to plug in the heater in my 5 gallon
betta tank, since it was summer and the temperature im my house (and the tank) did never go below 78.
But, it started to get cold and I connected the heater... hm... the temps are not going below 78, but they arent around 80 like they are supposed to with a heater...
I bought this heater because it said: "for 2-5 gallon aquariums" and "it raises temp up to 4 degrees" which is enough in my house for the betta tank, but for some reason I dont feel like its doing much

again, ive been careful and temps arent below 78 for Balthier.. but....
the heater is a Hydor Mini 115v 60Hz 7,5w.
should I get another one? again, I might just be paranoid but still...