pH troubles...

[lindz18]

My FC level was 1.5 and when I done my pH test it turned purple... Two days before pH was in normal range. This was right before I added 4 lbs of stabilizer (new fill after liner replacement) and liquid chlorine (it is now way cheaper than 8.5% bleach at Walmart!). What has caused my pH to change so fast?

 

[mikemass]

Aeration? SWG? If neither, then what else have you added? Is your TA high?

 

[Mr Bruce]

Do you have any water features like a waterfall? Lots of splashy kids?

In the end it really doesn't matter, it needs to come down to the 7s to be safe to swim and for equipment. Target for 7.7 so if you overshoot it's not a big deal. Baby steps for pH adjustment.

 

[lindz18]

Well, false alarm guys. I must have had a mis whack testing yesterday because it is a beautiful 7.4 this morning. My 3 yo toddler was helping me. Lol. I may have misadded something testing.

My numbers:
FC 4.5
pH 7.4
CYA 70
TA 60
CH 30 (isnt this ok for vinyl?)

I am seeing a tad bit of cloudiness in the deep end... Any help on how to resolve that?

 

[mikemass]

Numbers looks great. Do you have any CC's?

 

[Mr Bruce]

The minimum FC for CYA 70 is 5. You should get it to target now. Pool School - Chlorine / CYA Chart

I would bring it up to ~10 as the sun is going down and do an OCLT. If you don't pass, it's slam time.

 

[lindz18]

Already done CC is 0 Mike

 

[pooldv]

Yes, that CH is fine for a vinyl pool.

Jumping on chlorine soapbox
It is very important to maintain FC above minimum level for your CYA level at all times, [FC/CYA][/FC/CYA]. When FC drops below minimum the pool becomes unsanitary because the pathogen, bacteria and virus kill rate is too low to effectively prevent person to person disease transmission, especially in kids. Keeping FC above min also prevents algae, but chorine's #1 job is to sanitize the pool.
Off box

Spent some time at the TX coast last weekend that has numerous cases reported of flesh eating bacteria, as well as other stories of ear aches and other problems. Chlorine is your friend.

 

[lindz18]

I am so tickled to have a CYA of 70 :-o If you guys remember I was one of the ones with a CYA over 200...

 

[dfahrion]

FYI I've had the same thing happen on my pH test once, looked like sudden unexplained pH rise out of range, but next morning pH was lower than normal (I added some acid without thinking to question the test first, luckily I did take the baby step approach and didn't knock it too low!). I am also using a K-2006. I had to investigate what happened and figured it out. If you do not fully rinse the vial between the chlorine test and the pH test, you get funky colors in the pH test making it look really high. I now rinse multiple times just to be sure.

Agree with others your cloudiness is because your chlorine got too low, you need to keep above minimum to avoid, and probably SLAM to get clear it up now. I failed and let my chlorine get too low a couple of weeks ago, I thought I was OK because water was still clear so I just bumped back into normal range and continued as normal. Two days later I found green stuff growing out of my pool light! Once that was all brushed the pool was quite cloudy (looked like a hotel pool!) My first SLAM (We've only owned the pool for 3 and my first opening wasn't a proper SLAM) went fast but I wasn't out of range for CL for more than 2 or 3 days at most either.