After one use, 12 11x14 inch prints in a gallon of perma wash, the next time I go to use the PW I find slime floating in the solution. It it gray green and looks like dead skin. I suspect it may be residual from slime that develops in my washer but I do try to keep the washer clean. I periodically wash the washer and its partitions and allow it to completely air dry after each use. I also only use one tray for the perma wash to avoid contamination. Any ideas as to what causes the slime in the perma wash? Thanks.

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