High Salt but similar TDS Question

[rwijnbelt]

Newbie here.

For a while my relatively new Pentair IC40 has been flashing that the salt level is too high. I have done multiple tests:
- IC40 diagnostics says 4800ppm
- Saline Aquacheck says about 4300ppm
- New salt meter says 4500ppm (it also says TDS is about the same, which seems strange)

I have asked my Pool guy numerous times about this, but he keeps claiming it's good, even though I have seen his Aquacheck test strip show the similar value of 7.1 ==> about 4100.
He keeps saying he's not adding salt, so it cannot be too high. I have been trying to explain that salinity cannot just come from adding pure salt, but also evaporation and possibly other chemicals.

2 questions:
- Should I drain my pool to reduce the salinity?
- How can the TDS be almost the same as my salinity?

 

[JamesW]

TDS - Further Reading

www.troublefreepool.com

 

[JamesW]

If the meter has a salinity reading, you should set it to read salinity (NaCl).

If the reading is calibrated to a 442 “Natural Water” solution, you should convert the reading to salinity.

1,050 ppm 442 solution is about 1,500 Microsiemens Per Centimeter (µS/cm) (aka micromhos/cm), which is about 750 ppm in units of NaCl as seen on the below graph.

3,200 ppm NaCl is about 6,000 microsiemens per cm, which is about 4,900 ppm if the water was from a source with a different composition.

Since most of the TDS is from NaCl the TDS and the salinity are the roughly same.

Using the TDS setting on an electronic meter for a salt pool is not appropriate.