Various color growths in substrate!

[JR8999]

Is this bad? Should I do anything about it?
Running fowler for now. Reef later this winter.

 

[cloak]

It's normal, however the black could be an indication of something else. (Hydrogen sulfide)

http://reefkeeping.com/issues/2005-12/rhf/index.php

 

[Teenreefer15]

all those colors are normal except for the black i see that cloak said it could be hydrogen sulfide which sounds right. Read the link he posted that website has great advice.