So I am looking at ways to cool my nutrient reservoir. My ideal solution would create a snap-in water temperature regulator that simply uses a temperature probe, 110VAC outlet, and a pair of hoses to connect to any system. Here's what I've got planned so far.. * Controller $38 * Elements $17 * Chilling block $15 * Active heat sinks (x2) $26 * Pump $10 * DC Power supply $35 My plan is to thermal glue three of the elements onto the water chilling block. Then use the two heat sinks to actively cool the reverse side of the elements. I would then mount this chilling reservoir to the side of the nutrient tank, connect the pump to pull water into the cooling block from the resevoir. When the pump is turned on, it would suck water from the top outlet of the chilling block, which would create a reverse pressure system pulling fresh nutrient solution out of the reservoir. The block would be slightly tilted so all the water will drain from the bottom inlet back into the reservoir when the pump is turned off. Are there any better solutions out there? Any feedback is welcome.