We took one of our birdsnest, the brown one, and dipped it in lugol's idodine solution and they started squirming and dieing off immediately. I tried to get some pics but they aren't real great, but I will post them soon. From what I could see, after they came off the coral they looked more like worms with legs, mini centipeeds or something. They are about 2mm long and 0.5mm wide.