Originally Posted by Kurt_Nelson
...Everyone (rightfully) originally latched on to the fact that it didn't appear that the salinities were equal across the charts. The way it was presented, it appeared that the same samples used to assess how much moisture was in the sample was used for the charts. After a few folks on some other boards talked to the testers, it came out that it wasn't the case... the charts all do reflect the same salinities...
This was my point in my orginal post (From the original thread) and it still stands, I believe. The test was *never* intended to test salt vs salt using a SG
as a control point. That is, they measured out a specific *quantity* of each salt placing the brands head to head, toe to toe based on what the reef keeper should expect on average in each vendors salt mix. Most folks quickly jumped on the equal SG
/salinty bus because they did not read the paper, they simply looked at the pictures. If you take x amount of each salt brand then you measure for each element and other paramaters of interest, you then have an idea of what to expect, on average, for that salt vendors product. If you mixed to a SG
, then you are not measuring for a specific quanitified amount, equal across the brands anymore, instead, you are skewing the results of the various tests. For example, if I have to add 2 and half cups of IO to get 1.025 SG
and 3 cups of Oceanic to achieve the same SG
(At equal temp), we can assume we have already given Oceanic more mix from which to derive higher numbers. That is to say, the more mix I add to achieve some given SG
, the more trace elements, etc I also introduce into that vendors test. Thats no way to test anything side by side. In fact, what SG
does one mix to? 1.024? 1.026? What temp? As temp goes up SG
goes down, so its like chasing a rainbow.
Using equal amounts of all salts (And if everyone reads, you can see how they derived using some basic math, what amounts to use) allows you to get an *idea* of what you should expect *on average* through out an entire batch of a given vendors salt mix. As pointed out in the paper, there was noted concern that some numbers could be skewed due to the mix settling, etc, however, if folks read, they are quick to see why the Co chose not to re-mix the salts. Nothing beats reading the study for one's self and making sure to get clarification on each point we do not understand, else we may find ourselves the victim of mis-information...Or worse yet the perpetuator.
The reason I posted the link directly to the PDF is that the facts are clearly stated and charted for everyone to see (You need both to get the whole story). Of course we can be skeptical, that makes for great discussion and potentially more refined tests in the future. Could most of us do better with our Salifert or Red Sea test kits in hand? Doubtful. I can't remember the last time I purchased a good set of beakers, much less submitted them to a good acid wash for contaminations sake.
However, I believe like any other business that shows some gracious act of good will, there is always some hope of collecting on it.