How long can I be saving HCA? I use the powdered kodak HCA packets and just use a tablespoon per liter and have been dumping after every session no matter how many prints I run through because I was told that it oxidized in a matter of hours. Am I wrong in dumping it or can I use it for a couple days? I'm switching to the Ilford Permawash liquid because its all I can get here soon but I still have one last packet of Kodak HCA.