what are these?


New member
Please help me ID these growths. I think the one is yellow sponge and the other is green coraline algae but the LFS guy said he never heard of neon green coraline, and said it was green slime! I have numerous spots of this in my sump on the bottom glass as well as on various rocks..I don't think it's green slime! Sorry about the quality


  • yellow sponge I think.jpg
    yellow sponge I think.jpg
    64.3 KB · Views: 0
  • green slime or coraline.jpg
    green slime or coraline.jpg
    57.5 KB · Views: 0

Sugar Magnolia

Mother of Dachshunds
Staff member
RC Mod
Yellow sponge. Coraline algae comes in a wide range of shades, from green to pink to purple to maroon.


New member
I know they are both good just was wondering when the LFS guy said he never heard of a neon green coraline