I have used IO for going on 7yrs and never had a problem with, and the LFS I worked at has used it for over 20yrs and never had a problem and its the only salt they carry cause they actually use it unlike these places you repeat the claims of the manufacturer and have never actually used the stuff. As for some salts being enriched, thats where ya get bad batches of salt. You need to test your water for EVERYTHING everytime you open a new bucket just to be on the safe side. We all should do the same for any brand of salt because there is so many things that can go wrong during manufacturing that we would never know until we used it. They could have a new employee who knows nothing about aquaria and put too much of one thing that can cause tons of problems etc etc.