What is growing on my rock?

[aeromike9]

Noticed these green balls starting to spread over my live rock. They are light green with a short clear tube coming from the center. Have searched to try and id them but with no luck. Figured someone here may know what they are.

Here are a couple pics, hopefully not too blurry.

Thanks

 

[AlSimmons]

Sponges most likely. (harmless)

 

[aeromike9]

Thanks for the quick reply.

 

[mcgyvr]

Yep... Harmless and beneficial and very common pineapple sponges..
Bookmark.browse this for future use..
https://www.lionfishlair.com/hitchhikers-guide/
IT has most of the common stuff..

 

[aeromike9]

Thanks for that link mcgyvr. Pretty extensive list.