CYA & Borax with SWG

[Ian196499]

Hi

I’m going to be fitting a SWG and would like some advice on CYA level.
I have a pool enclosure which “sort of” makes it like an indoor pool so I maybe can get away with having a much lower CYA level as the UV load is low.
however, in the summer the sun does occasionally shine here in the U.K. ( when it’s not raining) and so we do open the enclosure letting in the sun.
So would it cause any harm to run the CYA at the bottom end of the recommended levels ( say60ppm) ?
Additionally I read that adding Borax is good for stabilising the pH. It seems that Borax is banned in Europe and so I can’t find anywhere that sells it! So is it a problem to skip the Borax and if so what do I need to watch out for?
Thanks in advance for any guidance.
Cheers
Ian

 

[duraleigh]

Skip the Borax.....no big deal. Borax is not used for stabilising pH, it is used for raising it.

Based on your description, a CYA of 40 sounds about right.

 

[Ian196499]

Thanks!

I read the “Borates in pools - further reading” where there does seem to be some benefit for adding Borate via Boric Acid.
I have found a source of Boric Acid (H3BO3). Based on my pool volume of 46kL I think I’d need about 10kg per PoolMath?
I have fill water with a very high TA (>200). So would this be beneficial?
Thanks again for the help!
Cheers
Ian

 

[duraleigh]

Borates buffering capacity has long been a subject of discussion. It is not an essential part of pool maintenance.

Some have reported significant benefits and others have reported virtually no affect.

It certainly doesn't hurt anything except a bit to your wallet.

It has virtually no effect on TA

 

[ping]

In your situation do not add borax to the pool, it will not help in your situation.

Borax slows down the rate of rise in pH and it limits the high end of the pH but the amount of acid to control the pH will be nearly the same amount. It takes more acid to lower the pH when there is borax in the water.

With the TA at 200, the pH will rise fast anyways no matter how much borax is in the water and it will only take more acid to lower the pH. That's why it is ideal to drop the TA down to 60 when adding borates. With that high of TA fill water you will not be able to keep the TA low enough without wasting a bunch of money on acid.

 

[Ian196499]

Thanks!
Given I’m already making changes with the SWG I’ll spend some time getting used to that and keeping everything in balance.
best not to change too many things at once so if I don’t need to do it then I won’t at the moment.

I’m using a plug in fountain and following the TFP how to lower TA guide to get the TA down before fitting the SWG - seems to be going in the right direction ?
cheers
Ian