What are those hairy things on my frogspawn skeleton?

[BubbleWrap]

I can identify some pineapple sponges. What are those white hairy things? Are those hydroids?

 

[vetteguy53081]

I can identify some pineapple sponges. What are those white hairy things? Are those hydroids?

Series of tube worms
While harmless are in a location where new heads would pop out
Remove from tank and place in small container of tank water and either scrub off with firm toothbrush or scrape off and return to tank