white pods hatching in salt water tank

Question
a couple weeks ago I began seeing white pods growing in my tank, the looked llike small white cucumbers with small feathery fans on the end. Last night we noticed the biggest one moving and this morning the fan-tipped end was gone and there was a hole in it. Something hatched out. Any ideas?

Answer
Hi Terri,
I cant be 100% positive without seeing, but I'm sure that was a feather duster(a worm). They will move occasionally as they decide to find a more suitable spot or reproduce. They can look, like tubes, pods, lumps, it's just a housing they make to protect themselves. They are really just a worm with a fan like crown around their mouths. The feathery fans are to trap detritus and wastes, they are filter feeders. Perfectly harmless, really good at helping maintain clean water, and can be quite pretty as they get bigger.