I have a 3/4 HP (1x4?) submersable pump in a 139' well. I think the pump is at 120' but not sure. My bladder tank is not large, I'm guessing 20 to 30 gallons. I have a whole-house filter on the ontlet side of the tank, and I change the string cartridge about every other month. In the last few weeks it seems that the water pressure at the faucet is getting less, and the filter change this morning didn't help. I believe I'm about to have a problem.
The system was put in service in September 1997, and I don't know the expected life of the components. My first thought was that minerals and sand might be filling up my bladder tank, or maybe the pump impeller is wearing out. Any suggestions?