What is this?

[biggie4jets]

Can anyone tell me what these are all around my tank? Looks like white areas with a white tub structure coming from it? See pictures

 

[jimc40]

Tunicates they are good filter feeders

 

[biggie4jets]

Oh perfect, thanks. Want to help me out with this nem question haha? https://www.reef2reef.com/threads/nem-help.743613/