Reef nutrition

Salt mix appears to be missing magnesium

A batch of Instant Ocean reef crystals appears to missing magnesium. I found this out when testing the tank and not getting detectable Mg with a Salifert test kit. Replaced the kit and same results. Tested a fresh salt mix solution and very low Mg (<500 ppm). A IO reef crystal solution is reported to provide 1320 ppm. Alk is testing around 11 which is the expected value. Just wanted to know if anyone else has had the same thing happen.

(I'm dosing the tank with Mg while I switch over to a new salt mix).
 
I once had the opposite problem years ago. I had a batch of IO with really high Mg. I forget the exact number, but it was something like 2000-2500 PPM. I had just gotten a new Salifert Mg kit at the same time this happened, so I complained to BRS about my bad test kit, and they sent me another one. Exact same readings. I finally figured out it was the salt mix. So, it is possible for a batch of salt to just have a really odd combination. I don't pretend to understand the manufacturing / mixing / packaging process well enough to understand how this happens, but I can imagine all sorts of ways. Thankfully, it seems to be relatively rare.
 
If they can’t get Mg in the right ballpark, being the 4th largest component of the ions in salt (besides Na, Cl, sulfate), what else are they getting completely wrong in there? What about all the minor and trace elements we aren’t testing for, but are assuming are in there as we use water changes to replenish them? Using IO/RC is like playing reefer’s roulette.
 
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If they can’t Mg in the right ballpark, being the 4th largest component of the ions in salt (besides Na, Cl, sulfate), what else are they getting completely wrong in there? What about all the minor and trace elements we aren’t testing for, but are assuming are in there as we use water changes to replenish them? Using IO/RC is like playing reefer’s roulette.
Honestly, using any of these salts is playing reefers roulette. It seems like every couple months one of them has issues, and it's not just the inexpensive ones.
 
Honestly, using any of these salts is playing reefers roulette. It seems like every couple months one of them has issues, and it's not just the inexpensive ones.
I don’t agree, I think you are making a false equivalence. Yes lots of brands have had 1 or more issues over the years. When IO has major issues it doesn’t make the news or even merit a shrug, since they have major issues all the time and don’t seem to care. When TMP had issues once, associated with a new production location, it made major news, resulted in a recall, and was dealt with decisively by TM. If you take any random sampling of salt from IO or TMP your chance of having some major problem is so much higher with IO than TMP I don’t even know how to estimate it. 1000x? 10,000x?

It’s like saying a cyanide-caught fish housed and shipped in terrible conditions and sold in a back-lot sale carries the same risk as a captive bred fish or one that has gone through a solid QT. Yeah they both can potentially have problems once they get into your tank, but the risk is not the same.
 
And yet IO is probably used in more aquariums than all the other brands combined.

Redsea also has issues with parameters off and on. People complain about fritz. I'm sure the others do as well.

Your analogy is a little extreme. These manufacturers don't extensively test every bucket. They test a tiny portion of a gigantic batch. They will continue to have issues here and there.

In reality, having Mg be off is a lot easier to catch and correct yourself than an unknown substance of unknown origin that may or may not be a problem.
 
And yet IO is probably used in more aquariums than all the other brands combined.

Redsea also has issues with parameters off and on. People complain about fritz. I'm sure the others do as well.

Your analogy is a little extreme. These manufacturers don't extensively test every bucket. They test a tiny portion of a gigantic batch. They will continue to have issues here and there.

In reality, having Mg be off is a lot easier to catch and correct yourself than an unknown substance of unknown origin that may or may not be a problem.
If one of those parameters is way off you should return or throw away that bucket, this happened to me with Seachem Reef Salt (Mg was low, and then turned out potassium was only 300ppm too). They discontinued that brand shortly after.
 
I have the opposite issue with IO RC. I have never tested the tank for Magnesium since setting up almost 2 years ago. Buddy said I should test for MG and multiple times they were over 1,500 with Salifest kit. I am dosing All for Reef so not sure if it has anything to do with it.
From what I read, it isn't a major issue if staying constant around 1,500. So I will let it be for now since the the tank is thriving.
 
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