I just purchased a new 2100 Krystal Clear sand filter pump (today) and it calls for 50 pounds of #20 sand. I went to one farm/pool supply store and they said they only stock #16 and that it might be hard to find #20. I called another pool supply store and they had it and said it was the only one they stocked so I picked up a bag. When I got home I notice that the bag only reads "nepheline syenite" and has no numbers on it at all to say what size it is (I need between .45 and .85) or that it's even for pools or that it is even sand. It only has a warning label about not inhaling the dust when you're pouring it. The woman at the pool store swears it's #20 sand and will work.
Is this the same as the #20 sand that I am supposed to buy? I just don't want to get it into the filter and do any damage if its the wrong stuff.