Red Crusty Algae?

[meathead]

Hello everyone,
My live rocks has this red hard algae on them. It's also on the power head and on the shell of my blue-legged hermit crab. I tried scrubbing it off but it is very brittle and hard. I tried scraping it and it is very hard.
What is this stuff?

 

[chinpokomon]

It is known as coraline algae it shows your tank chemisty is good you want this stuff.

 

[reefforbrains]

if its a reef get a tuxedo urchin. It will eat it down to next to nothing. I am probably the only person on the planet that doesnt like it, but I keep urchins just for this