RF, I wasn't expecting the skimmer to do much, either - but there's definitely foaming action going on - although I've added no conditioners until about an hour ago.. (see below).
I'm going to assume the live substrate has lots of live stuff in it - esp. since I tested again today - and now have ammonia... I also determined that I read the pH test wrong yesterday; my water actuatlly tests at 8.0 (which is, I'm told, is the pH of San Francisco water). I added 1 tsp of Kent Superbufer dKH to bring it up, per the direction of one of the LFS here in SF.
The water is, BTW, crystal clear now. Thanks for the kind words on the rock. There are a few advantages to living on the left coast - proximity to Fiji being one of 'em.