Why is my CYA spiking all the time?

[KatyPoolOwner]

I keep having problems with my CYA levels. Two weeks ago it was 180. I drained my pool over 5 days and got it down to 50. Then 4 days later I tested an it is up to 180.
How could it get so high again so fast? I am using chlorine tabs. Should I stop temporarily and use liquid chlorine? Thanks as always for all the help from the community!!

 

[ajw22]

How are you testing CYA of 180?

Tabs add CYA. Stop using tabs if you do not want more CYA.

Where are the tabs added to your pool?

 

[Jimrahbe]

K,

To go from 50 to 180 in 4 days is almost impossible unless you added a train car load worth of CYA.. A few tablets is not going to do this..

Something is wrong with your testing...

How are you testing your CYA level??

Thanks,

Jim R.

 

[KatyPoolOwner]

How are you testing CYA of 180?

Tabs add CYA. Stop using tabs if you do not want more CYA.

Where are the tabs added to your pool?

They are added through the automatic chlorinator that is part of my pool equipment.

 

[KatyPoolOwner]

K,

To go from 50 to 180 in 4 days is almost impossible unless you added a train car load worth of CYA.. A few tablets is not going to do this..

Something is wrong with your testing...

How are you testing your CYA level??

Thanks,

Jim R.

I am testing using my TF kit.
It was 180 on April 8th so I started draining the water every day for 4 - 6 hours.
April 9th 170
April 10th 160 then I added water for around 10 hours
April 12th it was down to 50
April 18th it was at 150.

 

[Newdude]

The 50 was a fluke.

 

[KatyPoolOwner]

The 50 was a fluke.

I thought about the 50 being wrong too. However, that would mean that spending 25 hours draining the pool had no impact - - that doesn't make much sense either??

 

[PoolStored]

When you do it the way that you are doing it, it is very inefficient, because the water mixes. To maximize the reduction, and minimize mixing, it should be done in one fell swoop.

See "no drain water exchange" here:

Draining - Further Reading

www.troublefreepool.com

 

[Newdude]

I thought about the 50 being wrong too. However, that would mean that spending 25 hours draining the pool had no impact - - that doesn't make much sense either??

Depends on the flow. A 1/3hp pump with 100ft garden hose is like running the kitchen sink and a 4 inch trash pump is like opening a fire hydrant.

And then how much it mixed comes into play also.