CYA high, should we empty the pool and refill?

[Tori91]

Hello,

We became owners of a house which has a fiberglass pool with sand filter.
We tested water at the suppliers store and they said CYA is too high and we should empty the pool and fill it with fresh water. They also explained risks of emptying the pool.
Are there any other options? Could we empty pool partially?

Thank you!

 

[tim5055]

It may be different in Sweden, but in the US not much credence is given to pool store testing around here. While you would think that a "professional" would be the best, unfortunately in most cases it is quite the opposite. Between employees who blindly trust the word of chemical sales representatives and high school kids working in the pool store for the summer you end up with poor results from their testing. Plus, the results of their "testing" is used to convince you that you need to buy things. Why do you think that testing is free?

But, what can you do?? We base our pool care system on accurate testing and only adding what the pool needs, when it needs it. To do that you need your own accurate test kit. As you are in Sweden, ouf favorite the TF-100 Test Kit ™ is not available to you. Lamotte makes a few test kits that have all the tests. You want one with the CYA test and the FAS/DPD chlorine test (not DPD, they are different).

If it turns out that the CYA is high with your testing, then yes, a partial drain and refill can be done depending on the number. How high did they say the CYA was?

While you wait for it to get delivered, you have a homework reading assignment. Start with these:

ABC's of Pool Water Chemistry

There are several items things every pool owner should know about swimming pool water. We share details on the basics of Pool Water Chemistry.

www.troublefreepool.com

Recommended Pool Chemicals

Which should I buy? TFP's recommended pool chemicals are cheap, easy, and won't unbalance your pool water.

www.troublefreepool.com

How to Chlorinate Your Pool

Before chlorinating your pool, you should know these simple tips. Learn the best way to add chlorine to your pool.

www.troublefreepool.com

So, welcome to TFP!!

 

[Tori91]

Hi Tim,
Thank you for your reply. They used Pool Scuba II test kit, what do you think about it?
Person who works at store said that level is too high even when pool water is diluted with clean water 50/50. Their test kit was showing a maxim 200 and what is over 200 it was just a '---' score.

 

[tim5055]

Hi Tim,
Thank you for your reply. They used Pool Scuba II test kit, what do you think about it?
Person who works at store said that level is too high even when pool water is diluted with clean water 50/50. Their test kit was showing a maxim 200 and what is over 200 it was just a '---' score.

We are not big fans of automated testing.. The Pool Scuba II basically uses color matching tests and then uses a photometer to interpret what the colors mean. Color match testing in most cases is inaccurate when done with the human eye and can be even more so with automation.

We like drop based testing that has a color shift, like red to green so you know when you have reached the endpoint. Look for a LaMotte 7022. LaMotte is a French company and their kits are widely available in most of Europe.

If you can put a number to the CYA level we can get you started on a partial drain and refill.

How does the water look?