Passive intake cooling

Ok countrymen, i have an idea. but before the idea, i made a box. It's a simple box, cardboard, 2x1.5x3.5, mylar lined, one 6 in PC fan for exhaust, an Aerogarden Pro 2oo Hood with 2 supplemental cfls. as basic as i could possibly make it. but here's the problem, i live in an apartment. and that is actually two issues in one. I can grow indoors bc i have no central air and it isn't feasible enough for me to justify using my window unit to cool the box (although...). so in light of that i moved the box outside in early march when it was fairly cool. plants LOVED the fresh cool air. now that it is july though, and these California days are getting hotter and hotter, my box has trouble keeping below 85 and it seems to be some sign of heat damage on my plants already. I've trashed many a grow due to overheating and have now finally decided to crack down and figure out a solution.

I've come up with the idea of using a modified Zeer Pot to cool the air being sucked into my box. but my skills of design are lacking today and all i have been able to draw up is a hollow pot. which mayb work, i just dont trust my high mind atm.

Or maybe some sort of wicking system like a mini swamp cooler. pillars of wicks for the air to pass around as it enters the box. It would raise the humidity, but my box has pretty good airflow so i dont think it would be an issue.

Or maybe a terra cotta air brick sitting in a tray of water. the holes in the brick would allow the air to contact more surface area, making it cooler. ooooo, possibly some louverd ones butted up in opposite bevels so it creates a light seal as well as creating more turbulence to transfer heat.