I had a similar thing happen in my tank - one night all the featherdusters (I think I had 6 or 7) started giving off "smoke" - I never gave it another thought, except a couple of weeks later I noticed my tank was literally COVERED in small featherdusters - on the rockwork, power heads, filter intakes, only my sand was clear of baby featherdusters!
Most grew into normal size featherdusters, which I gave to my friends who eagerly accepted them, a few didn't reach adulthood (Maybe not enough food in the tank to support that many?)
Not sure if yours will develop into featherdusters, as I do not know if featherdusters require 2 to tango :smokin:
