I am not sure on the ID of that, but let me ask you this; What is you ALK level at? When I was having a major bloom, it was do to the fact that my ALK was below sufficient. When I brought it up way beyond the NORM, 14dkh (very slow drip over mulitiple days), the alage could not handle the change and detierated. The corals became stressed, but nothing major. Also let me say that I "Only have softies and LPS", use you own descrission.
J.