Originally Posted by Reygan2
I'm just about finished buying all the equipment I need for now, but I'm wanting to purchase a backup heater. I really love the Aqueon pro's, but I don't know if I need 100 or 150 watt. I want the option of enough power to crank up the heat if I ever need to treat ich, but I also don't want to run the risk of boiling my fish if the heater malfunctions. I'm probably over thinking this, but I could use some suggestions.
When selecting a heater for smaller tanks up to 30 gallons, just figure on 5 watts per gallon of tank volume. For tanks larger than 30 gallons, three watts per gallon is enough.
For the large, longer tanks, I've found two heaters placed at opposite ends of the tank will heat it evenly.