What should I set my heater temp for in the summer? I have heard my Biocube 14g will tend to run hot. Should I set it for 75? Then set it for 78 in the winter? Please advise.

Through a controller my heaters are set for 78 degrees all year around. Also have a chiller set for 80 degrees all year around and have not had any problems. I live in Dallas where it often goes over 100 degrees during the summer months. This is on our 200 gal reef tank. By the way the lights even cause the chiller to kick in even during the winter on warmer days.

I would just set at 78 and leave it.

I would just set it and leave it. Put a thermometer in your tank and just make sure it doesnt get to hot...if it does freeze a 20oz bottle of H20 and plop it in the overflow to cool it down

I concur. Also since I got my Solaris I rarely have a problem with my tank getting hot enough to kick the chiller on. The exception is this time of the year here when it is really not hot enough to merit the AC but the house gets warm in the late afternoon.