Seasoning question -- different from the usual...

[rooneymurph]

First, as an aside: I want to say THANK YOU to the various members whose posts I've been reading concerning the seasoning of a humidor. I'm on Day 8 of seasoning my humidor with the bowl of distilled water; I've got two calibrated hygrometers (one in the humidor, one in my coolerdoor) and everything's going really smooth. The overall chunk of information I've gotten from people on here since I signed up has been invaluable -- so thank you!

For the main part of my question: I have had a bowl of distilled water in my humidor since the day I got it (eight days ago). Every couple of days or so, I have taken a quick peek just to check the water level, which has visibly gone down -- as I can surmise, A Good Sign. (Cue angelic choir.)

I hadn't looked since Friday, and upon just checking now, I've noticed that the level is down even further, and there are little specks of black floating in the water. They're not gnats, and the house is by no means dusty or dirty to cause a massive influx of stuff to fly into the humidor and end up in the water.

I'm not concerned as in "!!!" but I'm just curious as to what this is. Has anyone encountered this before?