The fan idea is the best. Let it blow on the surface of the water. The fish will be able to take 86 for a few days just make sure you have an airstone in there.
i don't see that people mention a fish tank cooler. There is a fish tank cooler at stores but mostly saltwater as most freshwater fish are better in warm water as ocean fish are cold. Anyways, what type of fish do you have? I think that would help. Fan idea i don't think so. I sometimes visit Arizona as i lived there for a time and my cousin in there has a tank. The icecubes causes thermal shock. Turn off all lights in the tank. See if you can move your tank with more shade or open area. Air!!!!!!!!! BUBBLES!!!!!!!!!! and the fish tank cooler, you should go deeper into that. Powerhead, to keep the water moving and allow more air to get in. What is the average temp of your house? and where do you live. Shade is the best in my opinion, fan i have so much trouble with that. I think that a fish tank cooler though is your best bet and lets hope that your tank will 
BINGO!!!!I put frozen bottles of water in my tank when it gets too hot sometimes. Just monitor the temp... I have never had any fish losses from it.
...i don't see that people mention a fish tank cooler. There is a fish tank cooler at stores but mostly saltwater as most freshwater fish are better in warm water as ocean fish are cold