You have an ultra-violet water filter from AquaSana. It is leaking water. What should you do?
Never have the electrical plug in an outlet when making changes! The UV light could blind you if you look at it when it is on.
Make sure the O-rings on the top and bottom are in good condition. Old rubber will not provide a good seal. They need to be replaced every year or two.
Make sure the quartz sleeve is not cracked. They are delicate and can break/fracture easily and inconspicuously.
Make sure the quartz sleeve's ends stick out an equal amount on each of the two sides of the chrome housing unit; the quartz sleeve is a cylinder. In our experience it must be exactly in the middle of the unit with the same amount sticking out of the unit on each side; if one side has more of the sleeve exposed than the other, a leak may occur.
You may need a new black plastic cap (with a spring) that screws on to the outside of the unit.
Even people who take considerable risk do not drink regular, unfiltered water from the tap. You may want a whole-house water filtration system. You can buy them on Amazon.