Sorry for your loss. Thank you for sharing your experience regarding this product. I can also confirm orenda pr 10,000 is not aquarium safe. I could not find much info on this product. Unfortunately I came across your thread after having a similar experience. I have dosed on a doser heavily diluted lanthium chloride slowly into my skimmer for years without negative impact. I switched to this product when previous product became no longer available. one single comparable diluted dose killed half of my tangs in 4 hours. All fish had labored breathing. Corals and invert not affected. I did water change aeration and carbon.