Can anyone ID this algae?

[dmolavi]

Anyone know what this dark purple/black algae is that's growing on my rocks? It doesn't appear to be spreading, and is much darker than the coralline growing on my rocks, though I've heard coralline can present itself in a variety of colors...

 

[ivan_dalmatia]

I have black sponge growing, looks pretty similar

 

[mr_X]

It could be coralline. It comes in many colors and grows sometimes in plates, other times in branches...
Look at this coralline, growing like a monti cap in my koralia-

 

[ivan_dalmatia]

It could be coralline. It comes in many colors and grows sometimes in plates, other times in branches...
Look at this coralline, growing like a monti cap in my koralia-

Wow, I guess you never cleaned it,You can sell that as coral lol

 

[Sniperhank]

Coralline like that grows surprisingly fast. I have some that is brown and grows like a weed. The red is much slower growing for me.

 

[dmolavi]

The typical purple coralline is spreading pretty quickly and once it appeared, spots are all over the tank, and growing. If this stuff is black sponge, I'll take it...free filter feeders