Cal-Hypo raising PH?

[fire29]

Shocking my pool, using this: HTH® Pool Care Shock Advanced which is 56% Cal-Hypo
Never used it before, normally use liquid chlorine, but stores around are out

My Ph has shot from 7.7 to 8.3 in a span of 4 days. Ive not added anything else. Anyone else seen this? Pool School app says C-H isnt suppose to raise Ph.
And before someone asks, this was tested with both an electronic tester and a Taylor test, same reading for both.

To me this is highly odd, as normally Im fighting low Ph not high Ph in this pool (which from what Ive heard is a little odd for a SWG, which is suppose to raise Ph, and hasnt been running much while shocking).

Already working on fixing it (mur acid) just wondering if anyone has seen this effect from this product. If not a warning to others.

 

[JoyfulNoise]

Cal hypo absolutely increases pH. The other 44% of it are solid compounds like calcium chloride, calcium carbonate and calcium hydroxide. The carbonate and hydroxide raise pH and all of the salts contained in it add to the calcium hardness. Every 10ppm FC added by cal hypo will raise the CH by 6-7ppm.

 

[fire29]

So does this need to get marked in the app? CH increase is on there, Ph is not.

 

[JoyfulNoise]

So does this need to get marked in the app? CH increase is on there, Ph is not.

It’s not easily quantified because cal-hypo concentrations vary quite a bit and calculating pH rise is very tricky. Most people don’t use large quantities of cal hypo because it can cause cloudiness. So for normal daily FC use, adding cal hypo will have no noticeable impact on pH.