SWG Operation - Lessons Learned

[SeanB.]

Our construction hasn't begun yet but our PB told us during our design session that we would use a chlorine floater for the first 10 days after filling the pool and then start up our swg. It will be a gunite pool with plaster. Is 10 days long enough, or should we wait longer?

Thanks.

[PatL34]

Sean, Welcome to the forum.

I would wait longer. At least a month.

Unless your PB has prescribed what you should use in the floater, I would use a combination of regular unscented bleach and trichlor pucks. The pucks will add stabilizer (CYA) until you get to a 60 - 80 ppm level of CYA, and then use bleach exclusively.

Add muriatic acid ONLY to maintain pH at 7.2 - 7.6, and monitor the TA until it gets to about 80 ppm. Then adjust the return jets upwards to maintain that TA level while you are still curing, as it will help to keep the TA down and the curing.

The calcium hardness (CH) will rise naturally as the gunite is curing, so if you have the ability to use water that is no more than 200 ppm CH as initial fill I would do so. If you have to use well water, which I do NOT recommend, then a temporay filter that has the ability to remove metals and CH, HAS to be inserted in the delivery line.

BTW, make sure that there will be no sand in the gunite mix, as this can lead to pitting of the gunite at low pH as it is curing.

Hope this helps with your deliberations with your PB, and good luck.

Pat