I had pumps and chiller outside before I moved and took that tank down. For noise and heat control it was excellent! I'm in Houston, so also nice and hot outside. Never had any issues with it keeping the tank cool, but I'm sure it made my electric bill go up some since it was outside in the heat.
Exterior (exciting, it's a box!)
Added vents to each end, using a window screen 'kit'
The guts (two Iwaki pumps, antique chiller, and a fan)
