heres a cool way to keep cool ........
https://www.reef2reef.com/threads/a-new-way-to-beat-the-heat.413518/
And Chrisnnemo if anything keep skimmer going to help add air to water . Ice from freezer in a bag helps a little Fans work great too . you want to blow across as wide an area as possible usually the display even if its 90 in my office my tank never goes over 79.5 of course the fans run constantly lol. Humidity plays a big roll as well . the more humid the faster your tank will heat up . I use a fan in the window to help that . Ive tried dehumidifiers , AC , chillers . the cheapest way is a plain old fan and it works .