MOD EDIT: I have moved this post/thread under your active thread on this subject. Please keep posts related to clearing up you pool in this thread for now...It helps us know the history -linen
This is my 3rd post on shocking this pool. Please take a look & tell me if I’m on track.
Learned to make sure FC is WAY above shock before OCLT, I dipped below shock level both on Fri(dipped to 12.5 ppm) & Sat(dipped to 18.5 ppm).
I’ve also kicked shock level from 21 ppm(per Pool Calculator) to 31 ppm(CYA Chart). Have been consistently above 31 ppm since Sat morning.
Couple of things... Discovered grass growing behind the top row of tiles. We removed the tiles, concrete & grass. Scrubbed, raised water level above the area, brought FC above 41 ppm for the rest of the day. Next morning(Sun) FC was 36 ppm, maintained around that level & above 31 ppm. Lowered water under this cement area, was afraid the crack leading underneath the sidewalk would contaminate the shock level. My OCLT went from 42.5 ppm @ 8:30 pm down to 32.5 @ 6 am this morning.
Also found paperwork from a previous owner for treatment of Mustard Algae, not sure if correct & it doesn’t have a date. I do remember seeing yellowish on the wall next to the ladder steps that looked like it washed there from the water current. This was before I began shocking.
My #’s as of 3/30, just before shocking process
PH 7.5
TA 120-130
CH I cant test as one of my regents for this is bad & I havent ordered
CYA 80 as of 4/02, brought down from 90 after much backwashing
FC 32.5 ppm as of 6 am, added 1 gallon @ 6:15 am & 1 gallon @ 10:30 am
CC .5 as of 4/06, will test again next round
Water looks clear to me but keep failing OCLT.
As stated before I’ve done lots of backwashing. Normal clean is around 14 psi, it hasn’t gotten above 15 psi except the first day although I did have to backwash to lower the water level yesterday.
Should I be treating for Mustard Algae? Or continue as I’m doing?
See photos below of the 9†deep end & the long cement crack running along the top half of the cement area.