Coralline grows everywhere but on my rock ?

[Quiverfull]

Grows on glass, grows on plastic. Alk 8.3, Ca 435, Mg 1425, NO3 0, PO4 0.05. Tank is 8 months old. Started growing on rock (old Fiji live rock), but then went away. Using ESV 2 part on a DOS. algae grows well. No urchins, only Astrea snails and blue leg hermits. Bare bottom. Any suggestions?

 

[Dan_P]

Grows on glass, grows on plastic. Alk 8.3, Ca 435, Mg 1425, NO3 0, PO4 0.05. Tank is 8 months old. Started growing on rock (old Fiji live rock), but then went away. Using ESV 2 part on a DOS. algae grows well. No urchins, only Astrea snails and blue leg hermits. Bare bottom. Any suggestions?

I have seen the same thing in an older aquarium. There might not be an answer to your question of why.

 

[splunty]

I have the opposite situation. Coralline is growing on all of the rockwork, but zero on the glass or plastic parts -- absolutely none. Tank is about the same age.

Regardless, keep that Alkalinity stable and Ca above 400 and it'll start growing to the point you hate it.

Curious, if you shine blue light on the rocks, do you see fluorescence where the coralline died off? I did. The dying/dead coralline would glow bright orange.