Silver plated out of fixer onto jug

[Eric Woodbury]

I hadn't printed on some time. My gallon plastic jug was grey on inside from the silver in the old rapid fix. Hypam. I've seen this before, but now it's happened with fix that fresh and little used and fresh bottle. Film and paper fix.

Hypam concentrate is a little old. I wouldn't think it would be affected.


What chemical reaction is happening to cause this?

Thank you.

[jp]

If you used the brown plastic jugs it'd still happen and you'd be blissfully ignorant. I use gallon plastic jugs too (get my distilled water in them) Happens with both TF4 and TF5 fixers here. It doesn't seem to affect performance; perhaps it helps to have the silver come out?

I got kicked out of high school chemistry, so don't put much faith in my scientific theory.. I think the plastic is more favorable to nucleation leading to crystal growth / solid deposition compared to otherwise stable liquid solution.

[Tin Can]

My 2 floating lid tanks, one 5 gal and the other 2.5 gal in translucent poly made by ARKAY

May be out of production, last week BH had only lids https://www.bhphotovideo.com/c/search?q=arkay%20tanks&sts=ma

Both tanks have very good poly spigots 2 inches above the bottom, the floating lid is perfect, the top lid seal well

The black silver and whatever collects at bottom, I don't disturb it until I replace the entire contents

Small tank for film

Large tank for paper

They usually, sit on a elevated plank so I can flow directly into trays

I reuse TF5 and test clear time every usage

I am not a chemist and don't care a whit, I only want results

I follow best processes by actual chemists