I cooked this up for my own use so I could develop my 2-sided X-ray film without the scratches you get in a tray. Knowing I would be using Rodinal 1:100, the math worked out to be 7cc Rodinal in 700cc water or therabouts. But there is no reason why the tank won't be just as good for standard film and chemistry. It only develops 1 sheet at a time, but that's what most of us would be doing with trays anyway. I sized it for my Kodak 8x10 hangers to just fit. I suppose other brands of hangers would do fine too. This one was a bit of a toughie. But on the third try I had all the bugs worked out and it turned out perfect. The big ribs you see are to stop the bowing of the tank walls exhibited on my second failure that had no ribs. The first one leaked. BTW, notice the tube on the end for a glass thermometer to slip in and actually be immersed in the liquid. Follow these instructions carefully, as my Neptune 4 Max does better layers when printing long items turned front to back of the print bed. Instructions: Use PLA. Turn down print speed to no more than 200mm/sec. Turn heat up to 210C. Fan at 50%. Infill 50%. Bed, 60C, No support. The job wil take 39 hours and use about 2/3 of a roll of filament. Shield printer from drafts. Be absolutely sure the printer is in proper adjustment. If out of adjustment, or cold drafts you'll end up with a leaky tank from poor layer adhesion.. I increased the wall thickness to 1.2mm from the default .8mm to help abate that problem. This is an stl, not a gcode, so you can use your own slicer. I used Cura with .4mm nozzle