As mentioned above I also use 4-6 liters of solution for 16x20 prints. My sink will hold five 11x14 trays but for 16x20 trays I use tray stackers. I bought them from Calumet @ approx. $80. You can place up to three trays in the space of one. For washing I have a vertical partitioned print washer that takes up to 16x20 papers and sits on the counter-top and drains into the sink. A tray siphon will work but look into making your own print washer with sheets of acrylic. I made my first one by copying the design from a picture. After many years of use I replaced it with a store bought one.

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