I recently Installed a check valve on the water line between my well pump and the pressure tank as I was losing pressure back through the well. That seemed to caused me to get water hammer in that pipe. So I Installed a water hammer arrestor in between the check valve and the pump and I still get a water hammer. What am I missing. Can anyone help me. :(

Water hammer is caused when moving water is stopped quickly. The water actually has momentum inside the pipe and slams to a halt, shaking the pipes and/or valve. What causes the noise; flush a toilet, turn off a faucet or the pump shutting down?

The check valve is in between the well pump and the pressure tank. I'm assuming the Check valve closing shut is the problem. Thats's why I put a water hammer arrestor between the check valve and the pump.

The check valve is in between the well pump and the pressure tank.
As a rule check valves are in stalled between the pump abd the well head or at the bottom of the well in a foot valve. The check valve's there to prevent water from leaking back from the pump losing prime which leads me to believe that you may have a foot valve installed if your pump retains its prime. I would change the location of the check valve and if that doesn't stop the hammer click on back and tell me about it. Good luck, Tom