Can you I D these

[paul01]

Have these growing in shaded areas of rocks

 

[Dsnakes]

Pineapple sponges. They're good guys. Simple filter feeders that come and go

 

[paul01]

Pineapple sponges. They're good guys. Simple filter feeders that come and go

Thanks
There is white ones and green.

 

[DSC reef]

Definitely sponges and they come in all sorts of colors.

 

[Maritimer]

Perhaps not pineapple sponges (which look like little yellowish pineapples), but sponges for certain. Valuable filter-feeding members of your cleanup crew and possibly a moderately important part of your system!

~Bruce