Measuring salinity

[Planeden]

What do you guys use?

[victoly]

refractometer.

[ckyuv]

Taste

[Planeden]

Taste

Do you have to correct that or nitrates and phosphates?

[Brooks]

refractometer.

[Neon Reefer]

Refractometer designed to measure Natural Sea Water and not Brine, otherwise you have to convert.

IE: 35ppt solution of NSW has the same refractive index as a 36.5ppt solution of brine

Also needed is a model that has ATC Auto Temp Control because a refractometer can not directly measure salinity but instead measures the refractive index of the water and only displays as a salinity measurement in PPM or SG. And since a refractive index of a solution does vary with temperature this makes the reading that you measure with a refractometer depenent to the temp of the meter itself, not the water being measured. It is the bimetal strip inside the instrument that moves the reading scale as the temperature changes to compensate for the change in refractive index.

Be sure to purchase or make a known calibration solution to calibrate the new refractometer. And it is better to calibrate at the area of use. Another words calibrate w/ a solution of 35ppm and not RODI water w/ a zero measurement.

[+Capt. Obvious]

Refractometer

[Planeden]

Dang. I was hoping someone would say hydrometer. I'm worried about my eyesight and have seen some reviews saying certain ones are hard to read. My eyes don't work well independently.

So, if hydrometers are woefully inadequate, I may have to get one of the digital ones.

Thanks everyone, and thanks for the breakdown neon reefer.

[Timfish]

Both. I have a refractometer but don't use it that often and don't leave it in my van where it would be subjected to wide ranges in temperature. I prefer to use SeaTest's float type hydrometer that goes from 1.000 to 1.030. There are some valide complaints that the float types can be inaccurate. The problem I see with SeaTest's is until it develops a film so small air bubbles do not stay attached to the arm it will be inaccurate. Once it's "broken in" I've found them to be very consistant. Keep in mind refractometers can drift and do need to be calibrated periodicly.

[Planeden]

Both. I have a refractometer but don't use it that often and don't leave it in my van where it would be subjected to wide ranges in temperature. I prefer to use SeaTest's float type hydrometer that goes from 1.000 to 1.030. There are some valide complaints that the float types can be inaccurate. The problem I see with SeaTest's is until it develops a film so small air bubbles do not stay attached to the arm it will be inaccurate. Once it's "broken in" I've found them to be very consistant. Keep in mind refractometers can drift and do need to be calibrated periodicly.

Thank you timfish. I will check that out.