We have a well and a water tank with a diaphragm. Our water pressure was getting low, so I checked the air pressure in the tank. It was a little low, so I added air. At first it was working well, but later in the day the water pressure dropped to almost nothing. I found that the filter between the tank and the house was clogged up with brown crud. I replaced the filter last night and it was OK. But this morning the filter I put in last night was filled up with the brown crud and pressure was almost zero again. This stuff must be coming from within the tank. I've checked the water coming directly from the pump and it is clear. I think the stuff is probably algae that I must have knocked loose when I added air.
Right now I have no filter in the line because I think it will probably just get clogged up again. The tank is 11 years old. What are ways to solve this problem?