pH Level for SLAM'ing

[clmsntiger1]

I have a question about pH level for SLAM'ing. I know pool school calls for a pH between 7.2 and 7.5 before starting the process. How does a higher pH (7.8 for instance) affect the SLAM process?

 

[YippeeSkippy]

I believe chlorine's killer power is optimized at 7.2-7.4 range.

Also, knowing that once you raise your FC over 10 that the pH test is invalidated you'll know your pH is in order if you've put it at that lower range at the onset of the SLAM.

 

[Mr Bruce]

Guess who:

If one is going to shock at high levels using a hypochlorite source of chlorine (bleach, chlorinating liquid, Cal-Hypo, lithium hypochlorite), then one should lower the pH first before doing so. Adding chlorine raises the pH. Though it will come back down when the FC level drops, you don't want the pH to get too high because it can precipitate metals that can cause staining, can cause cloudiness from over-saturation of calcium carbonate, and at much higher pH the active chlorine level goes down significantly.

Algae bloom while getting CYA down to manageable levels

 

[clmsntiger1]

Thanks for the replies! It sounds like it doesn't adversely affect the actual process of killing the algae unless the pH gets really high, but could impact the clarity of the water or cause staining.