will algae harm my fish?

[mouse]

hi, i set up a tank about 3 months ago with a yellow tailed and a 3 striped damsel, but on the crushed coral there has been a brown looking algae or something growing and i was just wondering if that will harm my fish? there has also been dried up salt deposits forming on the top of my tank and i was wondering if that was norman and what i should do with it? thanks

 

[the rock]

the rock says....
that's all normal, the brown dusting will likely subside and then you will have a green algae break, get some inverts like the crabs, shrimp, and snails to keep it under control