I know I probably should know the answer to this but I'm just not sure. I have a standard 180 with two corner overflows and a 60 gallon sump which is in the garage (directly behind the tank). I run the apex controller (as of last week) and put the temperature probe in the sump right next to the return pump (so it should be giving me the tempterature of the water that is being returned to the main tank. I put the temp probe in the sump for two reasons: 1. the apex unit itself is in my garage where the sump is and 2. I dont like the look of having all these probes coming out of my display. Right now I have two 200watt heaters, one in each overflow box. Would it be better to place the heaters in the sump also? or should i put the heaters in the display itself (which would look terrible) or just leave the heaters where they are? Thanks!