I use 5L of liquid in 16x20" trays and some training did the trick for me.
One hand on each side of the tray, pouring from one corner and using the right elbow to support the opposite corner. Most important is to avoid sudden movements as not to create waves.
I use a little less liquid (usually 3L) but otherwise, my method is pretty much the same, slow and steady. ...it's my giant, DEEP washing tray that can get messy emptying
My goal in life, is to be as good a person as my dog already thinks I am.
i just use lids for my stop n fix n only use 1L at a time in my dev as i rarely do more then 10 prints at a time and if i do i can just dispose of it with a bit of stopbath neutralizing any negative effects itll have further down the line
I use a 10 L bucket as an intermediate step, the same bucket i use for mixing filmdeveloper. I set the bucket on a lower stool and then empty the large tray in the bucket. From the bucket it goes into the containers, using a large funnel.