Calcium?

[B69CA]

Hello Board

Hoping someone can offer me some advice. 3 days ago, I had my pool drained and acid cleaned (a friend of a neighbor did it) and in fairness, it make a stunning difference.

The pool was refilled from the municipal supply going through a filter to remove metals etc - again the water looks stunning...

The person who did the acid clean, also balanced it for me the following day however I took my own readings using my TF kit - this is what I have

FC 14
CC 0
TC 14
CYA 90
TA 190
CH 160
pH 6.8 - 7.0 although I don't put much weight into this given the high FC reading

Pool is a 11000 gallon plaster pool with SWG.

I'm concerned about my CH reading however the guy who acid washed it said I should wait a week or two before adding calcium.

Right now I have the SWG off to bring down the chlorine - which is happening (2ppm over the past day) however I want to ensure the low CH level doesn't cause any damage.

I'm planning to let my kids back in the pool to get "splashing" around so that we can get the TA down and the pH up so that doesn't worry me too much.

Just looking for some thoughts and input.

Thanks in advance.

Jon

 

[jblizzle]

Realize that when the FC is high (>10) the test reads artificially high as well ... meaning you pH is likely lower than it should be.

What is the water temperature? And salt level?

With a low pH and low CH, you could be harming the plaster. I would get that pH up some sooner rather than later.

Also realize that the splashing around will not lower the TA, it will only raise the pH, which will then allow you to add acid again to lower both.

 

[B69CA]

Hi Jason - thank you!

Salt is 3000 and temperature is around 80 / 82 rising to 86

Do you think I should add some washing soda to rise my pH?

Cheers,
Jon

 

[jblizzle]

Plugging your numbers into PoolMath gives a CSI of around -0.83 ... less than -0.6 can be problematic for plaster.

If they do not want you to add CH yet, then I would keep the pH above 7.2 / 7.3 to keep the water from being so aggressive. Either get to aggressively aerating the water (which with the high TA should raise the pH pretty quickly) or use borax as that will only raise the TA half as much as washing soda.

 

[B69CA]

Thanks Jason,

I have the pool aerating now and the kids will be jumping in shortly so substantial aeration will take place )

I'll retest everything tomorrow and see where we are at. Nice sunny days too right now with the pool having at least 8 hours of direct sunlight so hopefully my chlorine won't take too long to get down to normal and enable me to test more correctly.

Thanks again as always for your help.

Jon