High Chlorine High PH

[Ksjeepgirl]

I've been an online lurker til now, this site has saved my sanity several times this summer. I attempted to swim Monday night, the chlorine odor is unbearable. I used a few chlorine pucks a few weeks ago until I realized my CYA was rising. I did add 2 bags of shock Monday night, other than night I use nothing but bleach.
TH 200
FC 10+ almost red with drops
PH 8.4+ almost pink n strips
TA 120
CYA 100

Been near 100 degree almost a week, pool gets 6-7 hrs of direct sun, temp. is 86. I drained it several inches tonight and refilled, no change.

 

[tim5055]

Well, the first question is what are you using for testing? If you have been lurking you understand we recommend one of the recommended test kits. You can buy a kit at a pool store, but again the pool store kits generally won't cut it. To effectively practice the TFPC methods, the FAS/DPD chlorine test is essential. All these kits contain that test while very few other kits do.

If you are using test strips your numbers are a guess at best, but 100 is the limit of the reagent CYA test, so you have to do a diluted test. While the full instructions are in the Pool School, here is the short version. Mix 50% pool water with 50% tap water. Use this mixed sample as your test water. If still at a 100 you will need to dilute more. Here is a great chart by JamesW to explain dilution rates and what you multiply the results by to get an approximation of your CYA level.

Pool water......Tap or distilled water.........Multiply result by

....1...................1................................2
....1...................2................................3
....1...................4................................5

My guess is you have to order a good test kit. "Chlorine" smell is really not the good free chlorine, but the combined chlorine oxidizing bad stuff in the water. My guess (I can only guess without test results) is that you have stuff living in the water and you are smelling the results of your "shock" and bleach trying to kill it.

Order a test kit and start reading while you wait. How much Pool School have you read? Start with these:
ABCs of Water Chemistry
Recommended Pool Chemicals
How to Chlorinate Your Pool

 

[SunnyOptimism]

Another point to remember - when your FC is that high (>10ppm), you pH results are unreliably because most pH indicator solutions and strips (blaaaah, strips bad, argh!!!) get chemically altered by the chlorine and read false high. So you can only reliably test pH when your FC is at normal target levels.

And I concur with others - the yucky "chlorine smell" is coming from chloramines which are the by-product of FC reacting with algae and organics to oxidize them. Chloramines STINK!

 

[Ksjeepgirl]

I ordered a TF-100, should be here tomorrow. My CYA is 30-50 now, no other change. Thanks for your help.

 

[tim5055]

I ordered a TF-100, should be here tomorrow. My CYA is 30-50 now, no other change. Thanks for your help.

Great!! I'm going to assume you did a water exchange to get the CYA down. Good choice on the test kit.

Looking forward to a full set of test result tomorrow. Keep reading Pool School.

 

[Ksjeepgirl]

The kit OMG!
Here's my results:
FC 21.5
CC .5
TA 110
CYA 60
TH 250

Let the fun begin, after I get the time. I have a family member in ICU, and driving back and forth everyday. Thank you again for all the help.

 

[JVTrain]

Numbers look good other than your FC being too high for maintenance mode. You're close to SLAM levels for FC. Let it fall down over the next few days and then always keep it above 5 FC. Target 7-8 when adding bleach. Once the FC drops below 10, check out your pH. Water is crystal clear? I would even perform a OCLT if you have time. Sounds like you're very busy right now but if you could test FC after sundown and then before sun up tonight/tomorrow that would let you know the health of your pool.

 

[Ksjeepgirl]

Numbers are looking better!!
FC 12.5
PH 7.8
TA 110
CYA 50
TH 250
I absolutely love the TF-100. Money well spent. Thank you so much for your help.

 

[pwrstrk]

Don't forget your PH test is going to read a false high with FC at 10 or above.
Keep letting your FC drift down to maintenance level's. That would be a target of 7-8 and never below 4.
A couple of days ago your CYA level was 60. Did you replace some water or could it be the test. The CYA test can be a little tricky until you get the feel for it. ?

 

[Ksjeepgirl]

I did actually. We had a few days of heavy rain predicted so I drained it down a bit. With me not being home much recently I'd rather have it a bit low than have a disaster with too much. Ended up not getting as much rain as expected and I replaced the water today.

 

[pwrstrk]

That's fine. It's in a good spot. ?