chuck,

I saw some paperwork the old homeowner left behind and the pool filter and pump seem to be from 1987 which would make my setup 20 yrs old as well!

I did the acid wash this evening, but i didnt let it soak overnight, just for an hour or so. I also noticed that my pressure gauge isnt screwed into the filter like the picture on the manual. It seems like the previous owner plumbed some pvc in an L shape so that the gauge is visible from the top. It also looks like he glued the gauge in, so I wont be able to open it and flush out the de with a hose like the manual suggests.

However the filter wash did the trick so far, the psi is holding steady at 10 when before i couldnt get it to hold at 15 for more than a minute.