Settle debate between a friend and I!

[JonoH]

Trying to load the video now, but looks a little like Red Turf Algae

 

[bubbgee]

Red Paint.

Actually, I agree. Some rocks are painted so they are ready for the reef. I got UV reactive rocks for blue light in my nano. It's painted pink that reacts to the blue. This must be just regular red coralline painted rock.

 

[Marco_99]

Thread 'Deep red encrusting coralline algae!!!!!'
https://www.reef2reef.com/threads/deep-red-encrusting-coralline-algae.158047/

 

[bluemon]

Not sure I get the point of this post. You say is it for a bet.

So do you know the answer (as in your tried scraping it off, etc…) but just want to see what the community thinks as a bet, which is fine.

Or do you not know the answer, but you are withholding information pertinent to a successful ID of the red substance for the sake of your bet?

These two things are contradictory and really isn’t helpful if you are purposefully trying to keep it “mysterious” as to not “bias the jury”

Do you want an ID, or do you want a betting crowd?

 

[halfpennyreef]

I’m certain it’s coraline, my friend is convinced that it’s cyano. It’s slow growing, encrusting, isn’t fuzzy and doesn’t scrape off. It came in on the shell of a crab. All the rock in the tank was originally purple/live, not painted. The video was supposed to speak for itself as it showed that scrubbing it with a nylon brush does not remove it.

 

[ChrisfromBrick]

sounds like a high quality problem as long as it isnt intrusive.

 

[Rocks reef]

Looks like red sponge.
Is it soft?

 

[halfpennyreef]

Looks like red sponge.
Is it soft?

It’s hard as a rock and doesn’t scrape off

 

[56longroof]

It would be very odd that cyano would grow like this, only on that rock, and so well…without being anywhere else

It would be very odd to be coralline due to color, and also, due to it being plating

I could see it being either but it’s unusual to me. My first guess was a form of macro like dragon’s breath

There is a red plating coralline algea. I have a very small patch of it in my tank.

 

[exnisstech]

It’s hard as a rock and doesn’t scrape off

I vote coraline. It doesn't brush or scrape off. The only thing that can get that stuff off of my rocks is an urchin. EDIT: unless it blows off then I lean toward cyano

Close-up

Same rock months later after adding an urchin. Lights out so I used a flashlight

 

[ToxicPaly]

Looks like Peyssonnelia algae

 

[VintageReefer]

There is a red plating coralline algea. I have a very small patch of it in my tank.

I have heard of this but never came across it. Definitely a possibility

 

[nickng]

(1) does it glow under actinic lights?
(2) is it hard and if scraped off with a scalpel it’s like flakes
(3) no fuzz on surface ie smooth hard surface ie not in the least bit spongy.

If all the above are met, it’s likely to be red coralline. I had it in my 1st reef tank but was slowly taken over by the usual purple coralline.
Red or orange coralline look stunning under actinic lights ie gives a fluorescent glow.

 

[MikeyZo]

From just the look, I say cyano.

 

[Dburr1014]

What is on the back arch of this photo?

Looks like sponge to me

Edit: after reviewing the footage, it's coraline. For sure.

 

[halfpennyreef]

(1) does it glow under actinic lights?
(2) is it hard and if scraped off with a scalpel it’s like flakes
(3) no fuzz on surface ie smooth hard surface ie not in the least bit spongy.

If all the above are met, it’s likely to be red coralline. I had it in my 1st reef tank but was slowly taken over by the usual purple coralline.
Red or orange coralline look stunning under actinic lights ie gives a fluorescent glow.

1. yes
2. hard but haven’t tried a scalpel yet
3. no fuzz, no sponge