Critter/ worm id

[duytran]

Are these harmful? Seen a few in my tank when light were out. Any help would be appreciated. Sorry if video and pic are bad.

 

[Subsea]

Welcome to the r2r. See if this link helps. Also consider a tank thread, it would help others to be more informed with comments.

Ron Shimek's Website...Deep Sand Beds

Dr Ron Shimek's Website - Information on animal groups, husbandry of coral reef aquarium animals, his passion for native Montana orchids, Ron's blog and online articles

www.ronshimek.com