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burtonpj48
02-16-2010, 03:47 AM
Has anyone ever used calibration fluid for thier refractometer? Im getting various readings when i use mine. I just wanted to know how well it works. Where in Calgary do you buy the fluid.

globaldesigns
02-16-2010, 03:52 AM
I use RO water, works well for me.

Coleus
02-16-2010, 04:12 AM
i use ro water, works well for me.

+1

Pescador
02-16-2010, 04:25 AM
From Reef Central

Over on the chemistry forum the consensus is that refractometers should be calibrated with a solution that has a salinity close to that of natural sea water. A lot of people are finding out that even though they calibrated their refractometer with distilled water, when they tested a calibration fluid their measurements were way off.

I'm one of those people. I've been calibrating my refractometer with distilled water since I got it. After reading those posts, I recalibrated it with a calibrating solution. My refractometer was off by 0.005. My reef's actual salinity was 1.021 when I thought it was 1.026. Quite a big difference.

That being said, Randy has written an article detailing how to make your own calibration solution using distilled water and table salt.
Pinpoint Salinity Calibration Fluid
(http://www.marinedepot.com/American_Marine_Pinpoint_Salinity_Calibration_Flui d_Calibration_Solution_for_Testing_Equipment-Pinpoint_Monitors-AM1437-FITECL-vi.html)

tlo
02-16-2010, 04:29 AM
although it is said to be better to use calibration fluid, I find it hard to come by (maybe its just my area) so I use ro/di as well. IF it was readily accessible to me, I would be using it though.