What is this tube like thing growing on my walls?

[loseriam]

What is this tube like thing growing on my walls? I have them all over my tank, in my refugium, and even inside the walls of my protein skimmer. They are about small about 1/4 inch. Not sure if they are good bad or just doesnt matter. Can someone please let me know.
here is the pictures I have taken.

 

[meowzer]

sycon sponges...aka....q-tip sponges....aka pineapple sponge....LOL
Harmless and will come and go as conditions permit....they are filter feeders

 

[loseriam]

Would that mean my tank is good that they are thriving or bad and that is what they thrive on.

 

[meowzer]

It would mean your tank is normal.....LOL......they feed off the nutrients in the water column, and usually show up in inconspicuous places.....

 

[snakeblitz33]

cute little buggers aren't they?