Borate

[dykes26]

Is there typically any borate level in plain tap water?

 

[chem geek]

No, there is not typically any borate in the water nor any cyanuric acid. It's possible that in some wells with certain runoff in fertilized area that one could find some cyanuric acid and in areas in the Central Valley in California there is Boron in the watershed. Check your local drinking water quality report for the presence of such substances, but generally you won't find cyanuric acid nor boron.

 

[dykes26]

thank you

 

[dykes26]

Also, because my city requires backwash of all DE filters how often can I expect to be adding more Borate to maintain the 50 ppm give the typical 1 month DE filter backwash and should I worry about Borate in the winter?

 

[chem geek]

I don't know your pool volume nor how much water you use in backwashing, but I suspect it's less than 5% of the pool water volume each time. So that would reduce the borates by not more than 2.5 ppm so after a backwash this could be added, but it's not a big deal. I'd wait for at least 3 months and then test the borates level. You most likely will be able to go an entire season without having to adjust borates.

You don't need to worry about the borates over the winter, but if you have rain overflow that dilutes the water you may need to add more in spring upon opening.

 

[dykes26]

Love this board! Thanks!

 

[PaulR]

Pretty much any comment regarding borate dilution and replacement would also apply to CYA.
--paulr