I have the old style bladderless galvanized air tank and submersible pump system. Somehow air and water are being pumped into the tank and eventually (~2 weeks) I have to drain the air out so that I can get water. This started happening after I replaced the check valve in between the well head and the tank. This fixed my short cycling problem but now I have this other problem. Do you think the check valve directly above the pump is not holding the water column? Any suggestions or comments would be great. Thanks