For me i pour the flourite over a small green netting than run it over tap water with the pail below so that all the very fine flourite particles will be in the pail. I did this until it's clean or not much dust.
I find this method very tedious, so i later pour the flourite which is properly spread out over the netting which i lay on the bath room floor than use the shower spray and spray over the flourite until it is clean. Once clean, i just pick up the netting with the flourite on it and tranfer it to the tank. This method is very much faster.

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