Hmm. In that case, I think I'll leave at least some of the water in during the colder months. I'm thinking now that perhaps having a few inches in the cover will mean that the rain water freezes and allows the pool water underneath to remain liquid. Might also act as a buffer to protect the cover from falling branches and such.

I have one more somewhat unrelated question I'd like to ask here, if that's okay?

When I closed the pool, I blew the water out of the in, out and skimmer lines, with a shopvac, as is outlined in numerous videos I watched on the internet about the closing process. I closed the skimmer line with a Gizmo.

However, today I was looking around the internet and I saw this:

http://www.poolsuppliessuperstore.co...FcuZ4AodPGMAjQ

...and now I'm wondering if I should have used one, and shopvaced the remaining water out of the skimmer (the line is cleared and plugged but water remains in the skimmer's basin)? I'm starting to worry that freezing water could damage the skimmer by cracking it.

Thanks again for your assistance!