HI! Just wondering...I have one 240 litre tank that is heated to 26 C. We only have 18 - 20 degrees max in our house, so that means that the heater is running pretty much constantly...So do you think it uses a lot of electricity? because it was suggested to me by my dear family members that we could instead keep colder water fish. But would that really make such a difference? Doesn't a filter and light use more electricity? We lso have one 60 liter tank, that is also heated to 26 C - does the heater in this aquarium also use a lot of electricity?