How long to get Borax PH increase test results?

[famdog]

My PH was 6.0 yesterday AM in a 13,500 gal. AG with clear water and: FAC at 3.0, CYA at 30, and TA at 0. I've mixed 12# of Borax in water and added to the skimmer with the pump/filter running in the last 20 hours (3 additions of 4# each time). Before the last addition this AM, my PH was up to 6.4. How long do I need to wait after adding borax to accurately re-test for PH? Also, should I wait until I get the PH up to proper levels via this method to start in with baking soda on my low alkalinity? I thought I read somewhere to wait 24 hours after adding Borax to begin adding baking soda.

[CarlD]

you can add the baking soda right now. Start with 1 pound, and wait 6-24 hours, test and add more as needed. May help your pH rise a little, too. Or you could use washing soda (soda ash) to raise both at once.

[duraleigh]

I would add 10 lbs of baking soda if you're comfortable with your test results. That Alk of ZERO is beyond my ability to address.

There is a close relationship between pH and Alk, however, and 10 lbs should be adequate to make your Alk (and pH) results move in the correct direction.

Hold on the Borax, put in the Baking Soda, circulate and retest in around 6-12 hours after adding.

[famdog]

Thanks for the advice, but there's quite a bit of difference between adding 1 pound now vs. adding 10# now. Perhaps I should start with a 4# box and go from there? Also, is it ok to just slowly dump dry baking soda or borax directly into my skimmer, or should I mix them in a pail with pool water first and pour that in the skimmer? Thx.

[duraleigh]

Dog,

Download the bleachcalc in any of mwsmith2's post...you need it.

10 lbs of baking soda will raise your pool to around 60ppm....still 20ppm lower than the recommended level....I'm saying 10 because I still suspect that test result for Alk

I'll bet Carl's post of 1 lb was a typo.

Put 'em both directly into the skimmer, slowly, pump running.

[famdog]

Dog,

Download the bleachcalc in any of mwsmith2's post...you need it.

10 lbs of baking soda will raise your pool to around 60ppm....still 20ppm lower than the recommended level....I'm saying 10 because I still suspect that test result for Alk

I'll bet Carl's post of 1 lb was a typo.

Put 'em both directly into the skimmer, slowly, pump running.

Thx for the advice.

BleachCalc won't work on my Mac.

[mwsmith2]

I'd start with 4# and see what happens. You can adjust upwards from there. Slapping 10# in there at once might not be a good idea! :D

Michael