It does look like a hovering UFO, to me. I've liked a lot of what you've posted recently. You've managed to make the mundane interesting, which is a difficult thing to do.
thank you all so much.
vpw: i think you might be correct on over-agitation. i'm using paterson tank/reel, spinning for 5 seconds every 30 seconds. i think i might go back to 10 seconds initial agitation, then 5 every 60 ...