Refractory was reading high....

[sutton6989]

Just throwing out the friendly reminder to recalibrate those testing equipment. Corals were looking mighty pale lately. My refractometer was 1.026

Tested water at jays and mikes today at 1.020......

Happy I found the issue and pretty quickly.

 

[dz6t]

I have found many people had low salinity recently due to mis calibrated refractometers. The problem all came from these meters’ user manuals called for calibration using RODI or distilled water. When these meters were calibrated with distilled water, they read high when using 35ppt calibration standards.
I am using a Refractometer calibrated with 35ppt standard and cross reference to a calibrated Hanna salinity checker.
Also, it can be a good idea to calibrate your salinity probe frequently if you are using one.

 

[sutton6989]

I recalibrate with rodi!!!

Maybe I should invest in 35ppt calibration fluid.

 

[dz6t]

How do you calibrate the refractometer the first time?

 

[sutton6989]

Rodi originally

 

[Rafanho]

I calibrate mine with rodi water and also with the 35ppt fluid...and both way work perfectly for me

 

[afboundguy]

MOVED TO REEF TALK

 

[dz6t]

I calibrate mine with rodi water and also with the 35ppt fluid...and both way work perfectly for me

Because you happen to have a good one.
Many cheaply made ones need to be calibrated with saltwater standard.