Ultra high off chart CYA value

[wverboom]

Hi all,

Had no issues what so ever in the previous year(s) but this last months are horrible with a lot of algae.
At first I had no clue what's wrong but after buying a Poollab 2.0 and testing the "cya" it became clear to me there is a problem.
The value was OR (above 100) so I did not really know how high is was. Tried to replace 10% water but the reading was still OR.
Replaced 75% of the water with fresh water and did a test again. Now it's 94! and still too high.
I'm not using the chlorine blocks anymore and switched to liquid and hope I can reduce this problem in the coming weeks by backwashing daily and replacing a bit of the water.
When looking at the free chlorine chart I need to put more chlorine in my pool as the CYA value is so high. Can we still swim in there with a value of 9 or 10 chlorine?

Thanks in advance for answers! Regards, Wouter

 

[mknauss]

You can safely swim in a pool as long as the FC is above the minimum and at or below SLAM level based on your CYA. You must also be able to see the bottom of the pool in the deep end of the pool.

Your difficulty is your testing method. We do not have confidence in the photometer style test kits. Only Taylor drop based tests are relied upon. They are available in Spain as we have members there that have purchased them.

 

[wverboom]

You can safely swim in a pool as long as the FC is above the minimum and at or below SLAM level based on your CYA. You must also be able to see the bottom of the pool in the deep end of the pool.

Your difficulty is your testing method. We do not have confidence in the photometer style test kits. Only Taylor drop based tests are relied upon. They are available in Spain as we have members there that have purchased them.

Oh ok. I bought this Poollab 2.0 tester as it's the best on the market as far as I could find.

 

[wverboom]

I will ask the local pool equipment shop if they can do a reference test on my water with a Taylor based test to see if it differs from my Poollab 2.0.

 

[Griswald]

Oh ok. I bought this Poollab 2.0 tester as it's the best on the market as far as I could find.

According to them...

 

[wverboom]

According to them...

I know it's all marketing. But for now it gives me a good indication of the values.
For now I'm trying to keep my chlorine level high enough to fight algae and in time the CYA level will slowly go down a little when backwashing and refilling. Keep my fingers crossed
Thanks!

 

[JamesW]

I will ask the local pool equipment shop if they can do a reference test on my water with a Taylor based test to see if it differs from my Poollab 2.0.

Make a sample of 50% pool water and 50% tap water and then test that for CYA and double the result.

Take 2 samples to the pool store, one pool water and one 50% pool water and 50% tap water.

The 50% tap water sample reading should be half of the 100% pool water sample.

 

[wverboom]

I allready tested the tap water to see if something was wrong with my test.
Tap water was 0! Tested the neighbours pool water as he is using chlorine blocks with CYA and his value was 50.
Will make some other test to see if my results are correct.

 

[wverboom]

Is the "Taylor K2006" a good option? I'm going to buy a Taylor testkit to have an extra opinion

Regards, Wouter

 

[Whynotme]

Is the "Taylor K2006" a good option? I'm going to buy a Taylor testkit to have an extra opinion

Regards, Wouter

Yep, the k2006 is what you need.

 

[proavia]

If you can, get the Taylor K2006C - as the "C" has the larger reagent bottles.
The standard K2006 comes with 0.75 oz reagents versus 2.0 oz reagents for the K2006C.

 

[Newdude]

The 2006 (no C) has small bottles which is particularly problematic for the FC test you'll use daily for a while.

You want the 2006*C*

 

[BelSplash]

I'll play the devil's advocate here and tell you that your PoolLab is perfectly adequate for testing your pool water. No, it doesn't require calibration. Photometers are so stupidly simple that they either work, or they don't.
However ...
The results are only as good as the operator. The same goes for the drop based test kits. Make sure you understand the limits of your reagents and tester. Perform all steps accurately.
pH testing only works with FC less than 10 ppm. If your expected FC level exceeds the range of the Poollab, dilute your sample with chlorine free water and multiply your result accordingly. CYA testing is inaccurate with any turbidity test, but gives a good indication.

Keep the test vials/cuvettes clean and free of damage (only wipe with clean microfiber cloths).

 

[Donldson]

I'll play the devil's advocate here and tell you that your PoolLab is perfectly adequate for testing your pool water.

Perhaps it is "adequate" (it's not), but seeing as those asking for help with water chemistry at TFP will be required to offer test results from an approved test kit, it would be considerably bad advice to tell someone not to get one of the appropriate kits.