The Nova slot processors are wonderful but not cheap. I have used them for more than 10 years. They work well with RC paper; I think there's also one that works with fiber-based paper, but have no experience with it. I have a four-slot processor that includes a wash tank - all one unit, small footprint for up to 11X14; they also make them for 8x10. They are not, however, for batch processing - one sheet at a time. As to funky 4x5 tank, you may be thinking of the Yankee. Google it and see what comes up.