Can anyone tell me what this is??

[ellismac]

It almost looks like spider webs on my rocks. Opaque white slimy looking cob web. Anyone got suggestions??? I first noticed it in a few spots now it seems to be all over the place!!!

 

[NowGlazeIT]

Sponge

 

[ellismac]

Sponge

Is it ok to have in the tank??

 

[NowGlazeIT]

Is it ok to have in the tank??

Yes sponges are great filter feeders

 

[ellismac]

Great thanks so much. I’m aware of the orange/yellow sponge but I was nervous of this one