White stuff

[Picaso]

Hello everyone I have grown some weird White stuff on my LR it grows like a fungi on the rock but has raised holes in it like it's filtering the water and also grows ln lines traveling across the LR dose anyone know what this is is it good or bad? thanks

 

[Kurt_Nelson]

Sponges. Good things, in my opinion.

 

[Picaso]

Thanks

Thanks they have spread like mad mostly on the base rock