posted last week to Tom Barr. He said to email Seachem. I did and they are very helpful. I received three different emails from three different people. Marine Depot on line carries FLourite Black (not sand) and also Seachem put me in touch with several local dealers
I've seen in person the Black Flourite Sand and IS very fine. I chose the Flourite Black, it is same size Flourite Red. I should have my FB in by next week.