How much salt should I add?

[Jeffski]

My Intellichlor SWG says I need to add salt. The indicator light only tells me the ppm is less than 2500. I will get a test done on the water to determine the salt level exactly, but is there a formula to tell me how much salt to put in?

For example, my pool is 18' x 36', standard diving pool, so that's about 22,000 gallons I think. If the salt ppm is 2000 how much should I add to get it up to 3000?

Thanks!

[dawndenise]

ChemGeek posted this link to Michael Smith's Bleach Calculator which will calculate how much salt to add (about 183 pounds to increase your salt 1000ppm). Click on the "More Calcs" option on the Bleach Calculator to get to the salt calculations.

http://richardfalk.home.comcast.net/pool/BleachCalc262.exe

[Jeffski]

Thanks for the link.

[nater]

Jeffski,
I'd recomend this Salinity test kit from Taylor (or a similar kit from someone else) Since the SWC measure conductivity the actual salt level vs. screen reading can be different by several hundred ppm due to several factors. I use this kit to calibrate my autopilot as needed.

Also, the experts tend to agree that the salt test strips are accurate enough for our purposes, if you can find those instead.

http://www.taylortechnologies.com/products_kitinfo.asp?&MarketID=-1&KitID=2176

[jeffmull]

Whatever the results say, put in considerably less, test, and add as needed. If you put in too much, it's work to get the level back down. Better to err on the side of not enough, and add a little bit at a time.

Jeff

[waste]

Keep notes on how much you add and what the change is - that way in the future you'll know how much salt to add to raise the level 500 ppm (ex):cool:

[Jeffski]

Thanks for your help. I have continued this discussion and appreciate your feedback here:

http://www.poolforum.com/pf2/showthread.php?t=4969