Yah, but well my e-bill went up ~25 bucks/month when I had all my heaters on. Now I just keep the heaters on for the discus. (Heaters for 1250 gallons adds up.)
Though to keep my apartment between 75-80 I have to keep the air-conditioning on all year long... (I have it set to 75 when I am there and 78 when I am away.)
Most of my tanks are set between 78-80 degrees. I use the stealths they seem to run less which saves on the e-bill. And then of course my smaller tanks don't have any heaters, they seem to stay roughly at 74 degrees.