If you use a brush-on powder fly floatant with the initials FF you may be interested in this, especially if you have an empty brush bottle. This is an industrial supplier. The story is that they were surprised when they started getting requests for 1-quart quantities, since they normally sell in bulk. They started asking the quart buyers why they wanted this quantity. Turned out they were fly fishers looking for a bargain floatant.

One quart will last you many years! If you are refilling your empty bottle, be in a well-ventilated place and out of the wind.

http://www.epoxyproducts.com/silica.html

Enjoy!