How long does Selinium last?

[Matt5791]

I hva e some Kodak rapid selenium toner mixed 1:15 in a container.

How long does it last when diluted?

Thanks for any advice,
Matt

 

[ann]

we have some at the lab we have been using for over a year.

 

[blaze-on]

I save in a container as well but use a coffee filter when pouring back from tray-keeps the little black boogers out..

 

[Jim Noel]

With replenishment to keep the strength up, and filtering out the "monkeys", it will last for years. I last mixed fresh about 1990.

 

[George Collier]

Does anyone know the relationship, when toning papers with selenium toner, between color change, and the degree of "permanence"?
I made 2 liters a few weeks ago 1:20 (so 100cc of toner, plus a half a teaspoon of Kodalk to ensure alkaline). I toned 8 11x14 Forte V prints. The next batch, I had to add some straight toner to get the color change.
Was it exhausted, or was it doing the permanence thing, just not toning in terms of color?
If it matters, I use LPD developer 1:2, TF4 fixer, with a good wash between fixing and toning.