I have seen this article before, but I had forgotten the deatils.
My stock phenidone solution, in alcohol, lasts longer than the water-bissulphite one. I do not know how long (it finishes before exausting, I mix 200cc each time) but for sure longer than 6 weeks.
My stock phenidone fell apart in a matter of hours: 100cc water and 3g phenidone. I like the developer but will try Isopyoprl Alochol and..... how much phenodone do you use for 200cc?