Bebo77
Premium Nonpaying Member
<a href=showthread.php?s=&postid=7154041#post7154041 target=_blank>Originally posted</a> by Psyire
I would suggest reading this article by Randy:
http://www.reefkeeping.com/issues/2004-06/rhf/index.php
Here is the excerpt in which he refers to what I was talking about:
It is widely believed that only pure water is required to calibrate refractometers. That fact is true of many refractometers, and is certainly appropriate for routine calibration, but it assumes that they were manufactured correctly and have not been damaged since manufacturing. As refractometers used by aquarists become less and less expensive (with some now selling for less than $30), there is every reason to believe that at some point they will no longer be accurate enough.
The only way to be sure that a given refractometer gives useful information is to check its accuracy in a solution similar to aquarium water. I believe that all refractometers should be checked in this fashion when first purchased, and again any time there is a reason to be concerned. For example, an aquarist might be concerned if an aquarium that had been running for years at a salinity of 35 ppt suddenly reads 39 ppt.
So what I really should have said is you shouldn't use RO or distilled water if you want truely accurate readings.
you can calibrate using RO water.. i have read about it every where.. dont just do what randy says Psyire...