Refractometer or Probe.. Which to trust?

[tmccaffery]

My Milwaukee is showing 37ppt and Neptune probe showing 35. My milwaukee I calibrated using the supplied distilled water 1.000 SG. Neptune with Neptune 53,000 solution. When I have probe in solution it reads 34.9; Milwaukee solution test 25ppt. I am confused... Anyone?

 

[Tripod1404]

Do you have 35ppt calibration solution? I would test both with that.

 

[tmccaffery]

yes. I will test that

 

[rocsec1]

It has been my experience that the Neptune probe isn’t always accurate. I go by my Hanna and use the probe to,watch for changes in the reading.

 

[TxMex78]

It has been my experience that the Neptune probe isn't always accurate. I go by my Hanna and use the probe to,watch for changes in the reading.

I do the same as well.