Checking back in update and hope for some advice on remaining issues. It has been a month of attempting to SLAM, but I haven't been as consistent as I planned.
Problem #1 - Leaking at pressure gauge
Today I replaced my non-functional cheap pressure gauge with
http://tftestkits.net/Pressure-Gauge-Glycerin-filled-2-5-Bottom-Mount-p77.html
Afterwards, I have a pretty serious leak around the threading. I must have cross-threaded or something. I used tape and just hand-tightened. I put my old one back on and it is leaking now also but not as bad. I read something about using pipe dope instead of tape. Does this sound like the best plan?
Problem #2 - SLAM and levels
Backstory:
I was unsure of my numbers, especially pH and CYA but I figured to just move forward with keeping pool at shock level. I was about 2 weeks trying to keep FC at 12 because I thought my CYA was at 20. Then after no improvement, and later convinced my CYA was higher and targeted FC 20. I was rolling with this for 10 days or so but missed some days where it dropped back down. I've been backwashing and rinsing every 1-2 days, and brushing every 3-4 days. After 25 days of this inconsistent SLAM, I wasn't seeing any improvement. The green color had cleared up almost immediately, but I was left with a very opaque cloudy pool. Only 6-8 inches of visibility. My FC didn't seem to be dropping dramatically day-to-day. I'm confident there isn't much debris in the bottom.
Current State:
I had been discouraged and left it alone for 3 days while I waited on my new reagents, which came today. When I went out today visibility was much improved! Much less cloudy, now have around 5 ft visibility. Not really sure what caused such an improvement. We had a lot of rain recently, and I think it might have raised the pH which was really low. Could that affect it?
I ran my TF-100 tests while the chlorine was still low and now feel like I have some good numbers.
FC: 2
CC: 0
pH: 7.1
CYA: 40
TA: 45
I added enough chlorine to bring it back to shock level (FC 16). Anything else you think I should do at this point? Should I go ahead and adjust the alkalinity and pH up a bit?
Problem #3 - Pump pressure
After backwashing, my pressure / flow seems great. But when I check in 24 hours, the pressure is severely reduced. No clogs in the skimmers. After another backwash/rinse it is fine again. What is most likely issue here? The sand filter? There is another small leak in the PVC near the pump. Could that cause my pressure issues?