Warmer weather tank questions

[Coralgurl]

How many heaters do you guys run in the summer in your tanks? Over the winter I had to add a second heater to my 55 and started the 180 with 2 in march. Now that it's getting warmer, my tank temp is hitting 81+, I've turned the heaters down to 77 but it's not helping during the day as the house gets quite warm. Dumb question but is it ok to remove one out of each tank? Just nervous it's too soon. I've noticed the evaporation has slowed down as well. Thanks