Refractometer Calibration - Lesson Learned

[Dresden]

Thought I'd share a lesson learned recently.

I didn't know you should calibrate your refractometer with a special solution. I'd been using tap water for decade without realizing it. I had usually kept a pretty simple tank until recently.

Bought the calibration fluid and realized I had been running at less than 1.020. Slowly correcting to 1.025 now but I wanted to share in case it helps someone.

Maybe it is time to move to a digital salinity checker? Recommendations?

[Captured Moments]

Wouldn't it be OK to recalibrate using RO or distilled water and ensuring that it reads zero?

[Dresden]

I found a ton of topics and it sounds like the further from 35pt you calibrate from the greater the level of inaccuracy.

http://www.reefcentral.com/forums/sh....php?t=2644005