My problem is kind of a long term one so bare with me. Last year everything on my pool filter broke and I mean everything. I had to replace the pump, the sand and the laterals in my sand filter, the valve on top of the filter, and various pipes that had broken. At the end of last year, I had to close the pool with no success due to an unknown air leak. 2 weeks ago I reopened the pool to try to finish what I had started and I found the source of the air leak with a bit of troubleshooting and fixed it. Afterwards, i started to bring the pH level down and loaded in shock to kill 2 years worth of algae. The pool turned blue rather quickly but after these 2 weeks I still can only see less than a foot down. The pressure gauge on my filter shows an increase of 6-8 pounds of pressure every hour to an hour and a half from its resting pressure of abut 20 and i notice that the jets are barely flowing which leads me to have to backwash frequently. I only do so for about 15-20 seconds because I don't want my water level dropping too much and it's already beginning to get too low, but that amount of time appears to be enough to drop the pressure down to normal.
I just added some chemicals to lower my pH and raise my free chlorine level, but here's what the levels were before that:
FC: 0 ppm (I know its WAY to low, but that's why I added more shock today)
TA: 180 ppm
*EDIT* After adding the chemicals and waiting a few hours, these are the new levels
FC: 20 ppm
TA: 160 ppm
CH: 200 ppm
CYA: 70-80 ppm
I'm pretty new when it comes to fixing pools, but nothing I've done so far has fixed my problems. Any help would be greatly appreciated!