If
wiki's statement (
A Curding Tub has a 5x4 inventory for curds, a total of 20. Each curd needs 1L of milk and 0.02L of rennet, thus you only need 0.4L of rennet to fill a tub with curds.) is correct, then, obviously, we should be able to put exact 0.4l of rennet into it. In other case - it just leads to another annoying micro-management and timing.
So adding some 0.4l capacity rennet container would be more than good idea.
And option to pour out any amount of liquid from one container to another will be even more pleasant.
English is neither my native lang, nor my best side...