Add acid with new plaster

[Phillbo]

Your assuming I can speak with him .. My 3 attempts to contact him this morning have gone unanswered.

so, acid is bad for plaster ?


I guess a better question would be to ask what others have been told to do to start up a fresh replastered pool.

[mas985]

There are two ways that I know of to start a plaster pool. A chlorine start or an acid start. Most pool builders will use a chlorine start as this is a safer means of starting a plaster pool.

An acid start requires a lot of acid to drive the alkalinity to zero for about 3 days. The paster dust from the pool then dissolves and brings up the alkalinity and the calcium hardness. The PH must then be brought up to at least 6.8 after three days. The biggest problem with this method is that if not done correctly, it can trash your plaster.

The chlorine start is safer method but requires a lot more brushing. However, even this has it's variants. My plaster installer recommended this proceedure:

1) Fill pool
2) Add chlorine for 1-3 ppm.
3) Add enough acid for a PH of 6.8 and keep it there until all of the plaster dust is gone which is about a week.
4) Brush all plaster surfaces three times a day for a week then once a day for another week. Brush all plaster dust to main drain.

This seems to have worked pretty well since all of the surfaces are very smooth.

[Phillbo]

Thanks...... so it sounds like a couple pints of acid to help hold the chlorine would not do much harm..


How long until you started swimming?

[mas985]

I believe the rule of thumb is when all of the plaster dust is gone or 10-14 days. This gives the plaster enough time to fully firm up but I have heard of some going in earlier.

[bradjo]

Hi Phillbo;
Here are the most specific start-up instructions I could find online (they gave me chemistry levels) which was what I was looking to aim for. This url is from the National Plasterer's Council website (no affiliation).

http://www.npconline.net/start%20up.pdf

I have been following the instructions in here for an exposed aggregate finish. I have 3M Colorquartz and it's looking good. If you'd like you can see it here (pardon the landscape that's next!):
http://www.annonemoose.com/pool/DSC00705.JPG
Jo

[Phillbo]

I hear ya about the landscaping.. tomorrow I start a week off to paint my fences and lay in sod etc.. wish I could swim

[PatL34]

I would definitely use acid at this stage.

Pat