myreef, wanted to give you an update on the aqualogic unit. Right now it is hooked up in the basement under the tank. It is on a shelf (rated at 1000lbs) up close to the ceiling. I am going from the sump -> pump -> chiller -> sump. Right now I have the temp set for 80F. During the morning or night the chiller goes on for about 25 minutes then turns off. My tank is 180g with a 30g sump, total volume of about 200g, during the day with all the lights on (3) 250MH and (2) 140VHO, with a semi enclosed hood, the chiller turns on between 45-55 minutes then turns off for about 1 hour. This week it's been pretty hot and the ambient room temp with out AC running has been as high as 86F and the tank was nice and cool at 80F. I am using a medusa temp controller and in the manual it has a fairly long section in the back about chillers and how long they should cycle for, the medusa will wait until the temp goes up .6F above the set point then bring it down 1.2 degrees before shutting off. They state the chiller should always run at least 20 minutes to bring the temp down. If it is falling faster than that or turning on more than twice an hour there is a problem (i.e. not enough flow going thru the chiller, wrong placement of the temp probe). Anyway I like the aqualogic a lot. I seems to work great but it is not quiet. The fan blowing thru the unit is fairly loud and so is the condenser when it is on. It puts out a lot of heat that is removed from the tank, so I could not imagine putting this under my tank.
It's great not worrying about my tank temps anymore