washing soda but pH no go up?

[engrav]

So a cold spell and temp water down to 31 and CSI down to -.30
so I bought some Arm&Hammer washing soda (85% disodium carbonate)
did as per PoolMath and put in 16oz but
ph was 7.7 and does not seem it went up
I dissolved the stuff in water and dumped it in by the return
what am I missing?
thank you

 

[aussieta]

that amount will only raise your ph by 0.12
with testing tolerances
you could easily not see that

 

[engrav]

strange
FC6 pH7.7 TA80 CH375 CYA50 put into PoolMath
PoolMath adds Salt1000
Then PoolMath says 16oz will take pH from 7.7 to 8
by the way
TA did not change much either, maybe went from 80 to 90
now has warmed up so water temp 39 and whole CSI issue went away

 

[aussieta]

do you have poolmath set to25k gallons or metric

 

[engrav]

pic below of screen
also
at temp 38 the issue is not gone, CSI now -.28

 

[aussieta]

i used the section at the bottom
effects of adding chemicals
and typed in 16oz

 

[engrav]

why would it suggest .3 up top and .14 down below?

 

[mgtfp]

I wouldn't worry about CSI -0.3 for just a few days in winter. Even a few weeks wouldn't create a problem.

 

[duraleigh]

Two items a little off the subject, Why did you want to raise pH from 7.7? It is perfect right there

Secondly, 20 Mule Team Borax is better to raise pH. It has VERY little affect on TA and contains fewer residuals.

 

[engrav]

I wouldn't worry about CSI -0.3 for just a few days in winter. Even a few weeks wouldn't create a problem.

Am gonna do that. Stop fiddling. Water is now 40 and CSI > -.30.

 

[engrav]

Why did you want to raise pH from 7.7? It is perfect right there

Secondly, 20 Mule Team Borax is better to raise pH. It has VERY little affect on TA and contains fewer residuals.

Why pH? Temp was 31 and CSI -.31. I thought easy way to fix CSI was by adjusting pH. But 16oz washing soda did not do much. Now temp is 40 and CSI -0.28 so I guess the issue is gone. And from posts would seem best thing to do with a few days / weeks of cold water and low CSI is ignore it.
Why washing soda? Had some washing soda and did not have Borax and have never used it. But 16 oz washing soda in 25k did not do much. Next time if there is a next time I will try Borax.
Re: Borax
Have never used so pool is Borax zero. If I put some in does it remain forever? If so is that OK?
Re: PoolMath and effect of washing soda
Up top PoolMath (the browser version) says 16oz washing soda will move pH from 7.7 to 8. Down below under "effect of adding" it says 16oz will change pH .14. Why the difference, .3 one place and .14 the other?

Thank you

 

[engrav]

today temp 41 and pH up to 7.8 with a gallon of bleach and CSI up to -0.09
what was that line about mole hill into mountain?
next time will be sure eyeballs are aimed up and then go do something else

what about the two queries
should I have some borax in there
why pool math up top indicated .3 and down below .14

 

[engrav]

should I have some borax in the pool regularly, what would it add

poolmath (browser version) indicates 16oz washing soda will change pH 0.3 up top and 0.14 down below; why the diff?

 

[PoolStored]

@engrav I would suggest not being a slave to the machine. Adding 20 Mule Team will add a bit of borates, but over time, they will dissipate/degrade/disappear.

I'd say slow down. Let's reset. What are you trying to accomplish? Said another way, what are you worried about?

In the winter, for a few months, your CSI may go a bit more negative, but for a period of time, not an issue.

 

[engrav]

thank you
not worried about anything

previous posts for this problem resulted in a plan which is 1) aim eyeballs up 2) have a beer
so issue solved

but two little puzzles (to me) remained

 

[mgtfp]

Effects of adding doesn't consider the actual TA and pH for the effects estimation.

And as PoolStored just mentioned, there really is no need to micromanage CSI. If CSI is OK in summer, than going down a bit due to temperature over winter will not cause problems. The increase in reaction rates for dissolving calcium due to being further away from equilibrium will be more or less offset by reaction rates slowing down at lower temperatures anyway. -0.3 is not some sort of magical boundary. Your plaster won't really notice a difference between -0.29 (which you seem to consider to be OK) and -0.31.

 

[engrav]

thanks
puzzle 1 solved
puzzle 2 in 11 years I have never put in any borax, is there any reason I should be doing some borax

 

[PoolStored]

puzzle 2 in 11 years I have never put in any borax, is there any reason I should be doing some borax

To raise pH. Borax raises the PH and also raises the TA level just a little. If your pH is in the 7's, leave it alone.

 

[engrav]

thanks
1 and 2 disposed of

 

[mgtfp]

puzzle 2 in 11 years I have never put in any borax, is there any reason I should be doing some borax

Then you must be doing something right

I never ever saw a reason to actively increase pH. Maybe once in a while a tad too much acid, but nothing that wouldn't resolve itself with a little time and aeration.

When generally having an eye on how pH and TA develop, a situation that requires pushing pH up urgently shouldn't really occur. Particularly when avoiding trichlor tabs.