TDS in salt water pools

[Myron L Meters]

Hi, I want to buy one of your meters but need help getting the righrt one. I have a swimming pool service and repair business and need to measure TDS levels to determine when to replace water and also salt levels in salt water pools to make sure the reading the pool equipment is giving me is correct. I am not sure what the correct reading should be for a TDS check in a salt water pool. Usually we change out water in a pool when the water TDS is over 2000 in a non salt water pool. But in a salt water pool should the TDS reading be no more than 3000 plus the 2000. My brother uses one of your meters (model 512T5). Thanks for any help or suggestions to get the right meter.

[Myron L Meters]

 Here are a couple of links to articles that
go into the protocol behind what to do with your TDS reading.

http://www.southshoregunitepools.com/resources/pdfs/tds_salt_levels.pdf

http://www.bluescience.com/swimming-pools/posts/What-is-the-proper-amount-of-TDS-to-allow-in-saltwater-pools-before-recommending-a-drain/

The basic answer is you establish a baseline of TDS of source water
before salt, then of source water with addition of salt, and determine
when to drain based on the increase
over the source water plus salt measurement.

A pool's source water has TDS 250 ppm.
Salt or chloride in pool water as determined with a suitable chloride
or salt test kit is 4000 ppm.
TDS of pool water sample 6000 ppm.
TDS 6000 less salt of 4000 = 2000 TDS not from salt.
TDS not from salt less starting TDS of 250 ppm = 1,750 ppm TDS increase.
Not exactly time to drain but getting close - somewhere between 2000
and 2500 ppm increase.

512T5 is a good choice for you.  Here's a link:

http://www.myronlmeters.com/Analog-TDS-Meter-p/ah-ds-512t5.htm