Looks like maybe sponge. Good or bad?

[exnisstech]

I noticed these today and haven't seen them before. They look like a sponge but I've never seen them with the tentacle like pieces sticking out. They're soft and when pressed stuff comes out that looks like maybe spores. Kind of looks like what comes out of a puffball when squeezed. There's quite a few on one rock and they're on the back so low light but not dark.

Forgot the pic.

 

[PolypPocket]

Encrusting sponge, safe

 

[Baldyreef]

second vote for sponge!

 

[exnisstech]

Encrusting sponge, safe

second vote for sponge!

Cool, sponges are welcome. I run a cryptic zone and have white sponge but it's more like a mat. I don't see the openings like these have that remind me if a sea squirt I had

 

[Turkey head]

I had some that were similar or the same as that for a while. It thrived for a while then kind of disappeared with no significant changes to water quality etc.