tkos has a good idea. You can get an old low-rate computer power supply, mount it, and run cheap computer fans. It's an excellent low-cost solution. Also, when you have the fuge running, it should help out with the temp. As the water cascades downward and runs through the various overflows and the like, it will allow for evaporation (which cools) and increased exposure to systems of lesser heat, thus causing the water to pawn some heat into the fuge tank and then into the air. I'd still add some fans, and then get your fuge running and see how your temp goes.
125 gallon saltwater: 55gal sump, 4 Blue-Green Chromis, Purple Tang, True Perc, Firefish, Royal Gramma, 5 Ricordea, Bubble Coral, 15 Pulsing Xenia, Green Star Polyps, Deresa clam, Green-Tip Torch Coral (about 11 "heads"!), Orange Montipora Cap, Purple M. Digitata, Green Slimer Acro. Yongei, 3 Orange M. Digitata, Pink&Green Acro. Millepora