encrusting algae

Hello all, I am trying to identify a possible encrusting Algae/Bacteria. It is brown/black and competing with my coralline algae. It is encrusting in a strongly attached layer and has a similar feel to coralline algae although smoother. It doesn’t seem to be harming or competing with my corals...

This stuff looks is slowly covering my new rock. Scratches off rock, slippery texture, gsp seems to grow over it no problem. Is this an issue or should I just ignore.

Up until a little over a year ago, I always assumed all the hard, red encrusting algae we find in our marine tanks was just another variant of Coralline algae. Boy was I wrong! I eventually came across this site which made me realize that this "red Coralline" might actually be of the genus...

I am getting ready to set up a new 70 gal cube reef tank with "dead" live rock and I would love to be able to have as many colors and types of Coralline as possible. My question is: Does it ship well? I have seen scrapings of it for sale on eBay for example and was wondering if anyone has...