I have to agree with jtReef that you should put the fan on the timer with the lights - so that it's on when the lights are on and off when the lights are off - that way it's not cooling it off too much when the lights are off, but keeping it cool when they are on. That's what I do and my tank these days (in our 90+ temps we've been having out here in Colorado) has stayed at a nice 78 to 79 degrees
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55 gal glass tank, 2 power heads, wet/dry filter, protein skimmer, 50 lbs live rock, pair of tomato clowns, 1 royal gramma, 1 coral beauty angel, 1 six line wrasse, 1 peppermint shrimp, 1 skunk cleaner shrimp, 12 assorted snails (astrea/turbo), 15 assorted hermit crabs, green bubble tip anemone, red mushrooms, yellow polyps, 1 green leather, green star polyps, yellow toadstool |