http://www.aquariumadvice.com/forums/f12/tank-journal-225-cichlid-habitat-124880.html
My thread of a 225 with PFS as substrate - 4 50 lb bags of it. It took me about 45 minutes per bag, used a 14g tote, filled with about 1/4 of a bag, hooked a hose to a utility sink, sprayer nozzle, hot & cold on full, spray it full stream down into the sand to make it 'boil' for about 5+ minutes each batch, dumping out the excess murky water about a dozen times in the process, until it's reasonably clear, then I would dump it into a 5g bucket for storage & transport. What's funny is that whatever water is leftover gets forced to the surface, so after you're done, there's an inch of water on top of 16 inches of sand. When I scooped it out, it was pretty packed down. Great stuff.
Only #1 rule - fill the rinse container with a couple inches of water and THEN pour the sand in, very slowly. PFS dust is a health hazard, so you don't want to breathe the dust at all. Even then, you will smell it. Run a vent fan, and if you're really worried about it, wear a mask. I think that's really only a rule that you need to follow when sandblasting with the stuff, but better to be safe.