wattage

I am trying to select a water heater for a 3 gallon cube that I will be switching to soon and would like to hear your thoughts. Is there such a thing as an auto-on/off, "pre-programmed" aquarium heater? Or does it really come down to wattage per gallons and room temperature? Are there any...

I have an adjustable 200 watt heater but I only need 108 watts to heat the tank. Is 200 watts the maximum and I can turn it down to 100?

So, I recently got myself a betta fish. Currently it's in a one gallon tank (Being a college student I cannot afford/don't have room for anything larger). Currently the fish seems happy in it's tank, but where my college is in the mountains up north the temperature is dropping fast and my...

Hi! I'm looking to get a Hydor heater for my new tank as they seem to be very well recommended! I'm a little confused at which size I should get... my tank is 42 litres bare (about 37 or so with displacement etc.) and I'm thinking I need the 50 watt heater? Can anyone confirm this for me...