From about 1 month into this tank, I have had 3 or 4 small Feather Dusters. Of course being new I immediately posted pics wondering if they were good or bad. All replys said it was a sign of a healthy tank. Well, my tank must REALLY be healthy now. In the past week, we have seen at least 10 or 15 new ones. All are small and most are white but a couple look to be a bit purple. Just that was interesting.