White “stuff “

[Teke Left]

This white stuff has been in my tank awhile now & I don’t believe it is doing any harm just curious as of what it might be? Its only on the bottom half of my rocks the parts that don’t get any light .. ideas? Thanks!

 

[Crabs McJones]

Look to be sponges. Harmless filter feeders.

 

[Teke Left]

Sort of what I assumed but they’re everywhere... that’s what made me wonder