Potassium Iodide question of longevity.

[bobbysandstrom]

I'm making a .001% solution of potassium Iodide for use with the FX-1 developer. Does anyone know how long this dilute solution will last? I bought enough chemicals to make (4) 1-gallon kits. The recipe calls for very little amounts of the potassium Iodide. I will make 1 gallon worth of the developer and I would like to store the diluted Pot Iod solution to be used with each successive 1-gallon kit as I require more developer.

thank you
bob

 

[john_s]

There was an erudite post quite recently.

(there was a url link here which no longer exists)

 

[Alan Johnson]

In the original article about FX-1 ,BJP Jan27 1961,G.W.Crawley suggested making progressively more dilute solutions including 0.1% , 0.01% and 0.001% potassium iodide using water boiled for 3 min and cooled to about 90F.

Make future supplies from the 0.1% and the 0.01%. He said these solutions should keep indefinitely but reject the 0.001% after 2 years.