28gal JBJ HQI - Heat issues

[fishmanty]

So, I bought this system used, and have started it up for a few weeks. The temperature always looked to be good to me and in a decent range. Tuesday my controller from Aquatronica arrived and the trending for temperature is showing that me checking the temperature at 5pm every day (Time I get home from work) was fooling me (It read 80F each time). The trend is showing that I peak at 83F by 10pm (Lights go out), and dropping to 76F at 11am (Lights turn back on).

Questions:
1) Where can I get a cheap chiller that doesn't cost $400 (JLaquatics for 90gal capacity)
2) Anyone have any bright cooling ideas that I could use (Downside, increased evaporation)
3) How bad would this temperature fluctuation be on clowns and BTA's? Right now I just have some chromis and damsels in there while I ensure the water parameters are perfect.
4) Why can't someone invent an ATO that drops ice cubes into your tank instead of water?