Oly
Gold Supporter
If you are vigorously shaking the sample to mix the pH reagent then try just gently rolling, flipping the sample once to mix then match color. If you are using a speed stir then carry on and disregard this suggestion.
That would create only small effects on pH, nothing that would really be noticeable, especially compared to the aeration drift that should occur in the meantime.Looking back at test logs, my FC did go from 7 to 9.5 and then down to 6.5 in that timeframe. Not a huge drop, but did go lower.
Sorry for not responding to this. Never had any scale buildupOne thing that could explain pH dropping is scale forming. Your CH looks too low for calcium scale to be a problem. Could there be other minerals in your water? For example Magnesium? Is there any form of deposits building up in your pool?
Not typically. I did have it covered last week with a solar cover when we had a late winter spellDo you cover your pool? When mine is covered, the pH trends down in the low 7s, especially after rains. When I leave it open, it trends upward, to the high 7s.
I too find my pH to be remarkably stable. It’s a gift, enjoy it.I just wanted to close the loop here after watching ph and co tributes more closely this year, and thanks to everyone who made comments and suggestions. After another couple weeks I’m finding that my ph is really quite stable and doesn’t appear to actually drop any unless I add cya, but it also doesn’t creep up at all. I’ve had my small fountain hooked up for the last couple weeks flowing perhaps 1/3-1/2 of the return water to lightly aerate and it’s been rock-solid at 7.5. When I’ve had to add cya, I increase flow to the fountain and can balance the acid addition pretty well. It appears my “trending lower” issue earlier in the year was just due to balancing cya properly and not counteracting that with something to bring the ph back up.
Again, thanks to all.