The video explores various methods of removing residue fixer from fiber based prints, testing washing efficiency with pure water (no wash-aids). Tray method, circulating water, archival washer and ultrasound are examined, giving pretty much same result in 1,5 hours. Upper layers wash faster with water circulation for about 10-15 minutes, but dissolving thiosulfate (fixer) from fiber layer needs time, whichever washing method is chosen.
Research on archival washing of fiber-based paper:
>MYSTERIES OF THE VORTEX - MARTIN REED (.PDF)
>MYSTERIES OF THE VORTEX - MARTIN REED (.PDF PART 2)
>ILFORD WASHING SEQUENCE (PDF) (I personally do NOT get clean paper after a washaid and suggested 5 min wash, it takes 40+ minutes… but this document is out there and I feel like it should be on this page too)
Distilled Water . . . . . . . . . . . . . . . . . 750 ml
28% Acetic Acid . . . . . . . . . . . . . . .125 ml
Silver Nitrate, Crystals . . . . . . . . . . . . 7.5 g
Distilled Water to Make . . . . . . . . . . . 1 l
Stains from HT-2 cannot be removed and darken over time, so best is to wash a test strip along with the main print. Wipe the paper and apply a drop of HT-2 on a white area. Leave the print for a couple of minutes in subdued light and examine the stain.
A properly washed print will produce either a completely clear stain, or something between two lightest samples. It greatly depends on the paper, fixer and wash-aid, so try washing a sample print for 2 hours and test on it to have your personal reference.
I usually print from 2-3 enlargers and make 3-4 final copies of a print, which means a tray method (my 100% preferred when working with few prints) is not exactly manageable. I put all final prints into the tray with water pump and leave them there until the end of the printing session. Then they go to the archival washer with running water for 10 minutes. Then they stay in still water for 30mins, I renew water and rotate the prints/30 mins still water/ renew-rotate/30 mins still water/final rinse/Agfa Sistan (or alternative stabilizer)/dry.