Is this normal? SLAM

[iamtexmax]

Started SLAM yesterday morning (have been seeing that the pool has been losing a lot of chlorine past few days - so decided to SLAM)...Texas has been hot (upper 90's) plus the pool has no cover or shade - direct sun exposure (and the sun has been shining bright)
Before SLAM:
cya - 30
ph - 7.2
ta - 60
Yesterday morning brought FC upto 12 - and checked every hour and maintained - vacuumed and brushed (at least 4 times) - at 10.15 pm last night - FC was 12 - pool ran all night - this morning at 8.10 am - FC was 11.5 and CC - 0.5 (felt great as it passed OCLT) - water looks clear (not that the water was not clear when I started SLAM)
Decided to check FC at 9.30 am - FC was down to 9.5 (approx 2 ppm loss in an hour??).....is this normal....plan to check again at 11.30 am

 

[HermanTX]

With CYA of 30 and the sun we have been getting (I am in Houston area) the lost of 2ppm is not uncommon. If your pool is clear and no visible algae, it is most likely the UV. Suggest raising your CYA to minimum 40 or consider 50. I use LC plus I have added a couple of pucks in floater because of evaporation and refill of plain water (no CYA) to keep the CYA value at 40 to 50.

 

[iamtexmax]

Should I start adding acid now (current ph is 8.2) while letting the FC drop down to regular levels?

 

[mknauss]

If the FC is below 10 ppm, then the pH test is valid. Lower it with acid.