Dont buy a chiller ... use a heat exchenger

[Reef Pilot]

I am not sure you really have to waste that much water, as you can slow the flow just enough to cool the sump water. The reason I say that is that in a past house, we had a solarium off the deck that could get quite warm in the summer sun. So I installed a DIY air conditioner using a similar principle.

I got an old car rad from the scrap yard, and built a window like frame, complete with shutters (no ghetto look) to house the rad on one side of the solarium. On the other side, I installed a good sized exhaust fan (also found at a scrap yard), to draw outside air flow through the rad. I modified the rad ports to fit a garden hose, which I would connect outside. The output of the rad then went to a sprinkler for the lawn.

I controlled the flow with the outside water tap, and was surprised how low a flow was needed to provide very good cooling from the rad. We also opened the patio doors to the house, and it would be cooled down as well. I usually had the flow higher than needed for cooling, just to get enough water to make the lawn sprinkler work.

Anyway, the DIY air conditioner worked great, and the bonus was having my lawn watered, which was also needed during prolonged warm spells.

BTW, temps hit 31 C today here in Langley.