Hi Brent
I think you asked me about my chiller and ways to keep a tank cool. Your message disappeared in the Canreef upgrade and I haven't been able to reply before now.
I think on your tank it's more than just the lighting. A 180 is a big tank and should be able to dissipate a lot of heat. Especially when you AC the room.
If the room is 20'and the tank is 26-27, something is adding 6-7 degrees of heat to the tank. The fan over the sump is going to help for sure, so it's probably more like 10 degrees that is being added to the water.
I just don't think this is lights alone.
My first suspect would be your sump return pump? Is it air cooled or water cooled? Is it a Posideon?
Generally, the big wattage consumers are the big heat producers. Obviously the lights are one of the biggest, but I had 500 watts of MH about 6 inches above the water in my 90 gallon and one fan over the sump easily kept the temp down in the summer. In the winter I didn't even need the fan.
Maybe check if one of your heaters is stuck on? Take them out of the tank and see what happens?
Do you run a closed loop?
If it is a pump related problem, consider upgrading the pumps with the money you are prepared to spend on the chiller.
I actually did have a heat problem in my 90g. Between my return pump and two closed loop pumps my temp was pretty high. I shut down the closed loop and replaced it with powerheads. Problem solved.
Before investing in a chiller do some research on "cooling towers". The premis is a highly effective evaporative cooling technique. I've seen it used effectively where simple evaporative cooling wasn't enough. One of the great things about a cooling tower is that with a little bit of creativity and some dryer venting. you can direct the humid air straight out of your house.
Just my thoughts. Free bump.
