I have added a tub, glued from plastic sheets to my EDM machine:

and installed the windshield washer pump from a car to flush the drilling site with water. I got the pump from the scrap dealer around the corner for 5 euros. So that the water doesn't splash too much and the pump doesn't overheat during continuous operation, only 3.3V are applied to the terminals:

To make you see what difference the flushing makes, I had to prepare my microscope for under water operation. A short steel tube with a glass bottom does the job:

With an extension of the tub, I am now prepared to record under water timelapse videos with my microscope: