[sphelps]

I've always calibrated my refractometer using plan old RO water and although I knew some error would be involved I was under the impression the amount would be so small it would not make a difference. However I keep hearing more and more lately people stating after reading a few articles that this isn't the case and you need to calibrate your refractometer with some kind of calibration fluid otherwise you'll be off a noticeable amount.

Just wanted to share that after receiving some PINPOINT Salinity Calibration Fluid to calibrate my conductivity probe I stuck some in my refractometer and it's it reads exactly 1.026 as it should, not even out the slightest bit as far I can tell.

So regardless what articles my suggest it seems I can conclude that RO water is certainly an acceptable calibration solution. Anyone else try this and get similar or different results?