pegasus
Well-Known Member
Almost all of the negative reviews about Instant Ocean Reef Crystals point to the same thing... residue in the mixing container. I've dealt with it since I started in the hobby, and never really understood why it formed. I've heard different reasons, including it's likely due to an anti-caking agent that Instant Ocean supposedly uses to keep the salt from clumping. I can't confirm or deny if it is or isn't in the salt mix. But I do know why a residue forms in my mixing vat. It's calcium carbonate precipitating out of the solution. Before you get ready to throw your IO/RC away and look for a cleaner mixing salt, let me put your mind at ease. As plainly advertised, Reef Crystals has elevated levels of Alkalinity, Calcium, and Magnesium. When you mix your saltwater, the solution is over-saturated with these elements, which leads to precipitation. While this creates the annoying residue that we see in our containers, it doesn't mean that the saltwater doesn't have enough of these elements left to provide tissue-building material for our corals. On the contrary. Every batch of Reef Crystals I've tested, after a minimum of 24 hours, still contained high levels of Alk, Cal, and Mag. My theory is that Instant Ocean knows there is going to be precipitation, so they include enough extra of each element to allow for precipitation while still providing elevated levels of each. That's why I continue to use Reef Crystals...