I wonder if the Calgon is the silver sequestrant Knoppow is referring to. I got some interesting results when I added kosher salt to a Gainer-type brew of phendione, ascorbic acid and carbonate. The grains were small and very well defined little dots. Didn't look like a sulfite-free developer or a sulfite developer. Unfortunately, results were inconsistent and I had dichroic fog, so I abandoned the formula. But Calgon is readily available, so it's worth a shot.