80g/l Potassium Ferricyanide, 20g/L Potassium Bromide is my traditional bleach for most toners I work with. It can be be re-used. I actually use this old C-22 bleach for when I am short of the Kodak C-41/E6 commercial bleaches for c-41. In that application I replenish it 45m/l per 80 sq in, and keep the overflow for one shot b&w print bleaching. Dispose of this at HHW. I leave it out to dehydrate somewhat in the garage once it is too slow to reduce it's volume before spatula'ing it up and turning it in, in a well labelled bottle.