Salt study

[Kurt_Nelson]

Originally Posted by cmor1701d

Kurt,

I agree, but the charts and graphs should have been scaled for that. Otherwise you can't really compare one salt to another the way we would use it. ...

I haven't followed the thread over on RC, so maybe this has come out over there. Either way, I figured I should post this here so others have the info if they come across this thread later on.

It appears - even though it's not stated anywhere in the report - that all the ion charts, except for salinity and conductivity, were done with 35ppt water. So the salinity was equalized across the different samples. Don't know exactly how they did this, as nothing to this effect was stated in the report. I got this info from a reliable source (Boomer) over at Reef Frontiers. I normally don't like cross posting of messages between boards, but since you have to register over there to view any post, I'll copy/paste the conversation I had with him...

Quote:

[original question] Therefore I think it should of been tested at 35ppt instead of a determined weight. IMO I may be missing something completely!

{Boomer's response]

Yes you are, two thing missed.

1. Weight is done and should be done to see how much water is in the salt, i.e., 35 grams in 965 grams of water and the Salinity ** should = 35 ppt but you measure the salinity and it is only 31 ppt, thus there is 4 ppt water you are paying for

2. The assay they did was misunderstood by many from the way they wrote it. The actual ions measured where all done when all salts were actually at 35 ppt.

[Kurt's question]

Sorry for the off-topic drift, but a quick question about (2) above...

I understand your comment in (1) and why they tested the way they did... so you could see how much water you were buying. And that's shown in their first chart showing salinity.

But nowhere in the study did I find them saying anything to even hint that the rest of the charts were done with all the samples at 35ppt. I can understand why it was "misunderstood by many..."! Am I missing something, or are you just aware of additional information that wasn't published?

[Boomer's response:]

Kurt they dropped us (actually DR.) an e-mail to inform us of that, due to the posts on RC I would assume. It stated, in so many words, that the ion measurements where all done on salts that were normalized to 35 ppt. Only the Salinity and Conductivity gave different salinities due to the weighted 35 grams. At first we all thought as you as it was not stated anywhere, just as you posted. What bother me Chris and Randy is they really say nothing about their methods. And look at some of the odd ball ion levels like the Ca++ in IO I know of no one ever, in the history of IO, that has ever measure Ca++ that high in a sample test, i.e., + 500 ppm

[cmor1701d]

Thanks for posting that Kurt. I'm going to head back to RC for follow up. If we can confirm that most tests were done at 35ppt then the report is fabulous. I just wish they used a larger sample size.

[ccCapt]

What they did was 1st take the same amount of salt from all brands and add it to the same amount of water and check the SG. This way you can see how much salt you really need when mixing a batch yourself.

Then they dumped those samples and made all new samples of each salt all mixed to 35 ppt and then started testing.