Refractometer

[mg426]

Just wondering if its ok to use RO water to calibrate a refractometer instead of Distilled??

 

[Randy Holmes-Farley]

Yes, RO water is fine.

 

[mg426]

Thanks Randy !!

 

[Randy Holmes-Farley]

:thumbsup:

Happy Reefing.

 

[steve the plumb]

I didn't know that thanks.I just got my refractometer today.I should see if the unit is properly calibrated.According to the meter my salinity is .27-.28 a little hard to tell those dam numbers are small.

 

[Randy Holmes-Farley]

I agree that some are hard to read. The only way that RO water could be off is if the salinity is not 0 ppt. If it is higher, then there will just be an offset from 0 ppt.

Assuming tap water is a max of about 1000 ppm TDS, and RO takes out 95%, that leaves 50 ppm TDS. That can essentially be though of as a salinity of 50 ppm, or 0.05 ppt. That is too small of an offset to be important.

 

[steve the plumb]

my tds is at 0.It seems my salinity is a little high.I did a water change of 5 gal but not enough.I will do another at the end of the week.

 

[Randy Holmes-Farley]

How high is the salinity?

 

[steve the plumb]

from what the meter says .27 .28

 

[Randy Holmes-Farley]

Are you replacing tank water with with fresh water? It will take a long time to drop the salinity by replacing with normal salinity water.

 

[steve the plumb]

yes I am changing the water with R/O water.I will try to do 5 gal at a time.thanks

 

[steve the plumb]

I did a 10- 15 gallon water change and got my salinity back to normal .26 The meter is much more prcise VS the hydrometer.I thought my hydrometer was good but its off by 2.

 

[Randy Holmes-Farley]

:thumbsup:

Souds good.

Happy Reeefing.