Can adding salt bring CL to 0.0

[slange316]

27' round AGP, 17,100 gal pool. It has been perfect all year except CYA around 100-110 because I use trichlor pucks in the feed. In prepping to install my new SWG, I drained around 20% of water and refilled to get the CYA down around 80 -90. The yesterday, added 440lbs Morton Solar Salt. Checked CL before bed, it was around 3ppm, added around 60oz 10% liquid CL to bump it up. (I stopped using the trichlor to keep CYA down while I wait to put in the SWG) This morning, to my suprise, CL was 0.

Can adding salt do this? It has been real warm and humid, a lot of people in the pool the last few days, but I have been vigilant about keeping FC around 5ppm.

Slange316

 

[duraleigh]

Can adding salt do this?

The short answer is "No". Chlorine is consumed by sunlight and/or organics in your pool. Salt has no appreciable effect.

 

[slange316]

I guess it is just a strange coincidence. I think what has happend is I have been adding CL via a feeder all summer and able to keep up with demand. The last 2 days, I add liquid at night but not feed through out the day and could not keep up with demand.

 

[Butterfly]

.....It has been real warm and humid, a lot of people in the pool the last few days, but I have been vigilant about keeping FC around 5ppm.

If your CYA is 80 or 90, your minimum FC is 6 or 7. The increased temp + swim load will require more FC. I suggest you dose it to 12 FC in the evening, which is the high target for 90 CYA.

Also, since you dropped to zero FC, an overnight chlorine loss test is a good idea. If you should need to shock, the sooner the better. Having the need to shock with a CYA that high can be very frustrating and expensive.

If all is okay w/overnight test, I suggest you do not allow FC to drop below 7.

Once you get your SWG installed, of course, you should follow SWG recommended levels.

 

[slange316]

I also noticed that after adding all that salt, I have what appear to be hundreds of little white rocks on the bottom of my pool now. I assumed they were undisolved salt but when I got them out, they look and feel like small rocks. Has anybody every seen this? Could there have been some rocks mixed in with the salt?

 

[JasonLion]

A couple of people have reported small rocks in with the salt, but usually only one or two rocks for a huge amount of salt, nothing like hundreds.

 

[slange316]

This was a couple of hand fulls.

 

[slange316]

I had to add some more salt this morning so this time I dumped about 30 pounds in to a 5 gal bucket and mixed with pool water. Then, dumped that mixture into one of those mesh lounge floats and let it float around the pool so I could "filter" out anything that would not disolve, and sure enough, a couple dozen small rocks/pebbles. My guess is there are about 100 or so in each 40 bag.

 

[frustratedpoolmom]

You should do an overnight FC loss test and make sure your FC is holding (just in case you need to shock the pool).

 

[slange316]

Did that. All is good.