Well Pressure Tank-Maintenace?

Make sure the tank is not water-logged i.e. no water should come out of the Schrader valve when you press the valve stem. When tank is tapped/rapped on, it should mostly sound hollow/empty on the upper portion— except down near the pipe connection end it should have water in it. Shut the pump off. Shut the house main valve. Drain down the tank. Test the air pressure in the empty tank with a tire gauge. It should be 2 lbs. psi. lower than the "cut-in" psi number. Usually either 18, 28, or 38 psi (one of these). The cut-in psi should be marked under the lid of the pressure switch (electrical box near the bottom of the tank), either 20, 30 or 40 psi.

The best thing you can do to optimize the life of the tank is to make sure the air pressure is correct. You must check the air pressure with zero pressure on the water side of the diaphragm, as described above.