red live rock growth.


Active member
brown stuff on top looks like diatoms to me. purple/red stuff on the sides is coraline algae.


New member
Diatoms come and go as your tank ages. While many people have different recommendations on how to handle them eventually they will balance out and stop appearing as rapidly as your tank ages. They are neither good nor bad ( could be wrong ) the worse they ever did to me was dirty up the glass on the tank.

The coraline algae also comes with age and is a good thing, colors up your live rock and is used as food for some species.