[frolinmod]

When water cooling a camera, the fan just acts like a heater. Turn it off. On the other hand, if you want to make sure the camera stays above the dew point, leaving on the fan is a good idea.

You want to use room temperature water and as large a reservoir of it as you can. Don't chill the water (at least not below the dew point).

You also want to use a pump that preferably does not cool itself using the very water it is pumping or at least one that puts as little heat into the water as possible.