Just for general information on these vertical washers. David Vestal wrote an article a few years back where he had run extensive tests on all the washers on the market. His final conclusion was that, with the exception of the Cascading type washer, that most of the washers required well over an hour of wash time (some required up to 2 + hours) to insure that the prints were clean. Even the cascading type required up to 1 1/2 hours depending upon how it was loaded. Just food for thought.
Also - Les is correct when he mentions that extensive wash time will wash out the print brighteners from FB paper. And today all most all papers contain a brightener. So if your prints don't seem to have that "snap" in your highlights, this might be the reason.