I have been thinking that I will try this when I get eggs. If it works...it *seems* like it might take some of the guess work out with mixing. I saw a short video clip where Alex Hue had two deli's one with hatch rite and one with with vermiculite/perlite, anyway he poured a small amount of water in each. Then tipped the deli's: the verm/perl showed the water running out whereas the hatch rite retained and absorbed the water and there was none that ran out of the cup.