I picked up a jar in the natural food store near me, Nature's Pantry.

Just buy Fruit Fresh - white shaker can with a brite green lid sold in both the spices section and the canning section - at any grocery store if ascorbic acid is all you need.

Dave

Fruit Fresh, EverFresh, or vitamin c tablets crushed. 500mg. dissolve six to a gallon of water as a presoak.

Many vitamin C tablets have fillers and corn starch to bind them together as a tablet. Its very hard to measure such products unless you know how much of the additives are in it.

Cheapest price I have seen on pharmateutical grade since last year when I paid about $10.49 a pound. A little 4 ounce package of the Ball type costs about $5.00 or more.

Here is a link that might be useful: Ascorbic acid source $8.49 /lb.