What is going on?

[Davidtja]

This thread follows on from a previous I posted where I was "slightly" worried about over chlorination.

Just got a Poollab and its results are worrying - I know my pool water is over chlorinated as my poolman screwed it up when he winterised it (long story).
So my pool lab reads as follows - I have had to use 50% distilled water on all but CYA to get these results as they were otherwise out of range:

PH 17
FC 16
Total Chlorine even with distilled water out of range.
Alk 205
CYA 80

4 different brands of test strips however give me something altogether more acceptable heres the average but they are each within tolerance:
PH 7.8
FC 10
Total Chlorine 8
Alk 120
CYN 100

I also have Poolsense which I have not really used got working at end of season last year it reports:
PH 4.72
ORP 1153 mV

I am struggling to find a shop to do a test for me to corroborate these results (they all blame covid!).
And the decent test kits dont seem available in the UK.

Any advice ?

 

[PoolGate]

Chlorine is a consumable and continuously decays and leaves your pool water. That said, your chlorine level, based on your other numbers, is not high enough to be of any concern. With a CYA of 80, you should target a level of 6 (I recommend 8 or 10% of your CYA value) but it is safe to swim up to 31. The real question is are your test numbers accurate? Test strips are wildly inaccurate the best place for them is the trash. Pool store test results are not much better. The backbone of the TFP method is owner testing and pool care. Pool stores want to sell you products.

Can you get a high quality test kit with lab grade reagents in the UK? We recommend Taylor reagents.

The Free Chlorine and Cyanuric Acid Relationship

Managing your cyanuric acid and Free Chlorine levels is key to stabilizing your pool. Learn how these two items affect each other.

www.troublefreepool.com

 

[Davidtja]

Unfortunately much as I have searched seems no one does them in the UK - Those sending from US are hiking the prices to nearly £200 - I have already spent £150- on Poollab, which in Europe seems to get good reviews. I also purchased £200 Poolsense from SA last year - I'm HUGELY skeptical about its reading although it agrees Chlorine is high, it suggests Ph is half that of the average of the strips and quarter of the Poollab.
could a reading of Ph17 be correct even? In terms of the water it was a new fill at the beginning of last season its only ever looked crystal clear and never had a strong Chlorine smell.
When you say target a level of 6 do you mean Free Chlorine?

 

[mguzzy]

When you say target a level of 6 do you mean Free Chlorine?

Yes he means free chlorine... have you found this article yet? It explains how we approach Pool Chemistry
ABCs of Pool Water Chemistry

 

[PoolGate]

Unfortunately much as I have searched seems no one does them in the UK - Those sending from US are hiking the prices to nearly £200 - I have already spent £150- on Poollab, which in Europe seems to get good reviews. I also purchased £200 Poolsense from SA last year - I'm HUGELY skeptical about its reading although it agrees Chlorine is high, it suggests Ph is half that of the average of the strips and quarter of the Poollab.
could a reading of Ph17 be correct even? In terms of the water it was a new fill at the beginning of last season its only ever looked crystal clear and never had a strong Chlorine smell.
When you say target a level of 6 do you mean Free Chlorine?

Yes - Free Chlorine target level of 6 but safe to swim up to 31. Your pool loses 2-3 parts chlorine per day in season so even if it was a little high, it would reduce fairly quickly. That chart I posted above has recommended levels. Chlorine level depends on CYA level. So an accurate CYA is required.

pH of 17 is not possible. 14 is the highest which would burn you (very strong base). You should at least be able to get a pH electronic tester they are fairly accurate.