While poking around the Daniel Smith site, I ran across these. They’re called skin papers, and are basically replacements for the plastic/cardboard combo that comes in your ink can, and supposedly keep that unsightly crust from forming on top, without recourse to the no-skin spray. I’m off to order a box . . .
We had something like this at the first shop I worked in; I think they were just waxed paper, so we ended up cutting a bunch of our own. It did seem to work… at least keeping it from completely crusting over! Let us know how these ones work!