Anyone know what this is?

[beebedl]

I have recently seen these brown patches forming on some of my live rock and I'm not sure what it is and if its bad or good?

 

[cloak]

Lobophora algae would be my guess.

http://www.melevsreef.com/id/lobophora.html

 

[Sophie10]

Very hard to tell from that picture, bee.

 

[philosophile]

Could it be a red coraline? Can you poke it and tell is what it feels like? Scratch it. Does it come off easily?