You could use a ziploc with ice in it or if you have any bottles of water frozen you could put a couple in the sump. A small clip on fan blowing across the top will help also. The one thing you want to do is bring it down slowly.
Do you know what caused the temp to go up that high?
works really well. I use that along with a 1/10 hp chiller and it keeps my tank at 77 all day. doesn't even run much. Without the chiller this fan keeps my tank at 80 when my MH's are on.
I use a ten inch box fan mounted in my sump. it hangs from the top directly pointed over the water in the sump. I have in on a timer so when the white lights come on the fan kicks on. I keep a pretty constant 79-80 degrees with it. The draw back to using a fan is the increase in evaporation. I get about a gallon or more a day of evap with the fan on. Only about a 1/2 gallon if that with the fan off.
I drilled a 3" hole on the feeding led of my old 12g nano and hooked a computer fan to it then ran the wires inside the hood to the back. It worked great.
Good point Jeffmuse!! If it's the 14g biocube and your using stock pump. Pull it out and replace it with a maxijet 1200. I did that in my nano and it dropped the temp about 2 degrees.
Last night my tank was so hot my hogfish was sitting in the rock, I was afraid he was goin to die so I started looking at the pump. Well that thing was so clogged up that it was heating up the tank a ton more so i cleaned it for about 30 minutes. well my tank is now 78 degrees and my hogfish is swimming around and eating like no tomorrow!
I agree with Hnguyen that you should replace the pump if it is the stock one, but I'd replace it with a Maxijet 900 instead of the 1200. You only give up 65GPH of flow but you really lower the power consumption. Maxijet 1200-295GPH/20W, Maxijet 900-230GPH/8.5W.