Coralline growing on rocks but not glass

[Makara23]

All my rocks have about 1/3 to 1/2 covered in coralline and seems to be rapidly spreading, although there's still some brown and green algae mixed in. What's odd to me is that there is not a speck of coralline algae on the glass or plastic parts. I thought coralline grows on powerhead and glass first. Can someone confirm if this is actually coralline? Also, there seems to be some batches of deep red growth (seen in 2nd pic). Is this a Cyanobacteria, sponges, or a different strain of coralline?

Picture was taken under natural white light leakage from my house and windows, tank light was off. Rocks are live ocean rock, it started with lots surface life and debris, but it was nearly bare of coralline algae (seen HERE).

 

[Timfish]

Looks like coraline to me. FYI, coraline comes in many colors so the dark red, green and brown may all be coraline. Multiple factors determine growth so don't expect it to follow what happened in someone elses system.

 

[Hitchhik3r]

Funny. The same thing is happening for me and I have also been very concerned about the fact I don't see any coralline growing basically anywhere else. I have some very small specks growing on my powerhead but that is about it.

 

[Tired]

That's coraline. It may be coming back from stuff that was already on the rock, and/or it may be using the calcium and whatnot in the rock.

Honestly, this is a good thing. You don't want coraline on your glass, it's annoying to clean off. Just on the rocks is the best place to have it.

 

[SteveMM62Reef]

Do you have an Urchin? Maybe a Hitchhiker, Coming out at Night. They will eat the Coraline off of the Glass First.

 

[Graemesreef]

Coralline is not going to grow on surface's that get regularly touched/cleaned. Thats why it usually starts to show up on hard to reach place's or even your power heads. Your rock looks great.

 

[Cthulukelele]

I agree with others. Just thank your lucky stars. Coralline growth on glass at rapid rate is a nightmare.

 

[vetteguy53081]

All my rocks have about 1/3 to 1/2 covered in coralline and seems to be rapidly spreading, although there's still some brown and green algae mixed in. What's odd to me is that there is not a speck of coralline algae on the glass or plastic parts. I thought coralline grows on powerhead and glass first. Can someone confirm if this is actually coralline? Also, there seems to be some batches of deep red growth (seen in 2nd pic). Is this a Cyanobacteria, sponges, or a different strain of coralline?

Picture was taken under natural white light leakage from my house and windows, tank light was off. Rocks are live ocean rock, it started with lots surface life and debris, but it was nearly bare of coralline algae (seen HERE).

View attachment 2980625 View attachment 2980626

You may have too much flow against glass. If any film algae - allow it to remain short term as coraline may affix to it

 

[Makara23]

Do you have an Urchin? Maybe a Hitchhiker, Coming out at Night. They will eat the Coraline off of the Glass First.

I don’t have urchins. Hitchhiker is possible but there aren’t very many things that can eat coralline, especially this fast?

 

[Makara23]

Coralline is not going to grow on surface's that get regularly touched/cleaned. Thats why it usually starts to show up on hard to reach place's or even your power heads. Your rock looks great.

You may have too much flow against glass. If any film algae - allow it to remain short term as coraline may affix to it

I don’t clean the glass all that often yet. Maybe once every two weeks. High flow prevents coralline growth?

 

[Makara23]

Thanks everyone for confirming! I guess no coralline on glass and plastic is a good problem to have

 

[Makara23]

Also, there seems to be some batches of deep red growth (seen in 2nd pic). Is this a Cyanobacteria, sponges, or a different strain of coralline?

Quick update to this part. I tried rubbing and scratching those dark red spots and it won't come off. It feels slightly rubbery. It's probably some kind of sponge, might be coralline, but definitely not cyanobacteria.

 

[BaliReefBox]

I would say bonus if its not on the glass, less and easier to clean