Replaster Start-Up - Total Alkalinity Spiked

[Zephyros]

I had my pool & spa replasted last Tuesday with Pebble Fina. The in-water acid wash was done Thursday / Friday. Since then PH and TA were fairly stable (7.4 / 120). The pool company is doing 5 day start-up maintenance, they brush and test the water once daily. I take full maintenance back on Friday.

Here is what is going on:

Monday:
pH: 7.4
TA: 120

Tues:
pH: 7.6 (1/4 gallon acid added)
TA: 130
The pool guy wanted to do the Acid Slug method to get the TA down, but I showed him the Lower Total Alkalinity article so he agreed not to. Instead I started Aeration with the spa jets and spa spillway (with the Intelliflo VS running on speed 4).

Wed:
pH: 7.6 (1/4 gallon acid added)
TA: 200

Based on the Lower Total Alkalinity article, I expected to see the TA drift lower with Aeration, but it jumped to 200, could this just be a normal start-up situation (although I thought start-up led to spikes in PH not TA) or is something else going on?

The rest of the chemical readings look like this:
CH: 400 (tested Saturday)
FC: 0 (recommended to not add chlorine until PH / TA are stable)
CC: 0 (recommended to not add chlorine until PH / TA are stable)
CYA: 0 (recommended to not add chlorine until PH / TA are stable)

I may need to add more acid at a time, the tech did not want to drop the PH to low and chance etching the new plaster.

Thanks in advance for your advice

 

[Melt In The Sun]

TA and CH will rise quickly at the beginning, and will continue to go up noticably for about a year. I think you need FC now! The pool will be a swamp long before the pH and TA stabilize.

 

[Zephyros]

Thanks, I'll get the chlorine going.

Do you know why the TA would spike right after I started Aeration? Seems more than a coincidence since PH did not go up?

 

[jblizzle]

I think the spike was a coincidence based on the plaster not the aeration.

Re-read the article. The aeration does not LOWER the TA. The acid lowers the pH and TA. The aeration RAISES the pH.

If the acid was not dosed to lower the pH to 7.2 or so, it may not have pulled the TA down much to counter the rise due to the plaster.