Please Help Identify white stuff growing on rock

[maroma]

Notice this white stuff growing on rock and sand.

before I had

white slim still have. few.

 

[cracker]

1st pics look like sponges. The last pic .I think is bacterial & called Chrysophytes with a big maybe. ? I had this slimy stuff along with real low nutrients P04& No3

 

[Scopulum Zombie]

Sponge perhaps? That what it looks like to me.

 

[Chavin20]

+1 on Sponge

 

[declanisadog]

I believe sponge as well. My tank was covered in ones that looked just like that at one point. Are they rubbery to the touch?

 

[maroma]

have no put my hand on tank

13.5 been using nopox 4ml