Thinking about a refractometer.

[GrampaDon]

Believe this>> I still use a 5yr old swingarm SG box. < seriously

I'm ready to pick up thishttp://www.bulkreefsupply.com/store/products/test-kits/refractometer/refractometer-for-reading-salinity-w-free-calibration-fluid.html They seem inexpensive enough.

I feel comfortable they work great ,but I just want to know....do they need to be calibrated very often or not.??
Should I just get extra calibration fluid now.?

Reason im asking is stupid, I need RO filters anyway + I almost always try to order enough to get free shipping.


Link didnt work. Its the BRS 39$ refractometer.

[Reefmedic79]

I've never needed to recalibrate mine after the first time.

[jagr200]

You can calibrate with distilled water as well. Most actually recommend that.

[Browserz]

I always thought you shouldn't calibrate with distilled water..

[bamf25]

Best thing to get is a pre mix calibration solution (sea water salinity) for your refractometer to set the high number not the 0 number. It is more important that the number you are measuring too is correct than your zero point, if there is and problems with the instrament.