The only other SeaChem. Some have had issues in the past with the Salifert. Second, there is really no need to test for Sr IMHO and others, as there has never been shown any kind of biological need for Sr. Every year I go look and nothing. The reason has been Sr is in the skeleton and where people get this idea from. Thus, they must need Sr. Sr in the crystal growth of Aragonite is just a substitute ion for Ca. Sr is in th water and fits real nice into the crystal lattice. The amount in the water is directly proportional to that in the skeleton. This is so set that climatologists it use it to determine ancient ocean water temperatures. Dr Chris Maupin who is on here, i.e., Reefs.com is one of them. Dr (also most) Chris Jury also. One thing I often point out is if we are going by this, maybe we should start to sup reef tanks with Uranium, as the amount of Uranium in a coral skeleton is many times higher than NSW. Lastly, if the coral skeletons where made of Calcite they would have about zippo Sr, as it does not fit into crystal lattice like Aragonite. We would find Mg instead. More ancient corals us to be Calcite, not Aragonite, as the environment favored it but now favors Aragonite. Coral have been around for a few hundred million years.
