Would be nice to see a setup that is more "normal". A 12gal reservior is hardly normal nor feasable for the average user. I'm sure you get some cooling from the massive reservior. Do you have a way to check flow speed? I would also assume that the hotter the water gets, the faster it should move, thus increasing cooling through the rad. While you're at it, see if you could add a a single VERY SLOW moving fan to the rad to see how much, if any difference it makes. I'm thinking maybe a YL low at stock speed and dialed down.
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