Here is a thread I found where someone sent out IO salt for an icp. On his results Iron was not detectable, which is not the same as the results in the article linked by
@wmb0003. Which makes me wonder what results should be believed. I currently use Reef Crystals and I think I'm going to switch to the basic purple bucket Instant Ocean. I started off using Reef Crystals because I assumed it would help with trace elements, but I have started dosing those so I don't care if the salt has elevated levels or not.
If you send off a sample of IO for testing please let me know the results.
I submitted an ICP test for a 30 gallon mix of Instant Ocean sea salt. From the results Instant Ocean is low in Calcium, Potassium, Barium, Iodine, Molybdenum, and Manganese but is high in Tin. I am not sure why they read my salinity at 32 as I calibrate my refractometer with AquaCraft seawater...
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