Got some dead rock from a well establised tank, how to clean it?

[Paphagar]

I recently got some live rock from a well established tank and it is covered with dead coraline (completely covered in white scale). I was wondering if I should try and clean this from the rock. I've seen people saying to use muriatic acid to clean old rock and I was wondering if this is the correct step to take.


Thanks for any info!

TJ