How to clean and store Crushed Coral(Aragomax)

JMO, but I wouldn't.

But, for those that would: a pillow case (an old one) works well. You can run water through it in the bathtub or outside until it runs clear, then spread out on a large tray to dry. Once dry, bag it up and seal tight.
 
Another of the things that I OxiClean to get rid of biofilms, rinse well (with no more stirring than is absolutely necessary - coral is friable and will abrade itself endlessly with heavy stirring), spread and dry as suggested, then heavy-duty ziplock bag store (usually double bagged).
 
OxiClean works by breaking down with the release of ozone, so it burns out anything organic. The breakdown broducts are harmless simple materials and rinse free easily. It is a grocery store item around here, in the aisle with household cleaning agents.

Peroxide is similar, much much more $$$ in the quantities required.

Bleach could be used, but is much harder to rinse free, especially in porous material such as coral, and the residues if not cleared could theoretically be reactivated after drying by rewetting. So I do like to use that for any porous material.
 
FWIW: The reason I wouldn't store crushed coral is that even after cleaning it, I'd want to rinse it before I used it anyway. Even stored well, I'd be concerned about dust or fungus, and would therefore insist on cleaning it again before puttin it in any tank. Of course I wouldn't want to store it without cleaning it, since that would be begging for problems. Rather than deal with cleaning it twice (before storage and before use), I'd just buy new and only clean it once, before use.

For using oxyclean: determine roughly how many gallons of water you'll need to completely submerge the CC, plus a little. Add one scoop (about 1 tablespoon) per gallon of hotwater, stir to dissolve. Add CC, stir. Let soak til water cools. Rinse well.
 
Same thing, a bit less concentrated and not heated. Bucket and cover with peroxide, allow to react overnight (well ventilated please) and rinse. Does not burn off as much gunk as does OxiClean IME, and many times the cost.
 
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