I'm on my third hatch. On my first two I was using chux (like used at hospitals, non-permeable on one side / absorbent on the other) over the grate when I set the eggs. I am worried I'm sucking moisture out of the eggs by doing that, so this time I put them directly on the grate. Its the plastic grate that comes with a Genesis 1588. I see it done both ways. Any advice?