What are those white stuff on my Corals?

[nicowboy]

Hey Guys !

Can you tell me what this is and if it’s dangerous?
I’ve already scrapped it about a months ago but it came back, it looks like feeder worms but not sure

 

[dwest]

I see pineapple sponges. Good.

 

[nicowboy]

I see pineapple sponges. Good.

Oh thank you so much

 

[Baylott224]

They are benificial they grow in dark areas don't need to scrap them

 

[Staghorn]

SpongeBob house. Your good

 

[nicowboy]

They are benificial they grow in dark areas don't need to scrap them

Ok thank you ! I can leave them then