help with bubbles

[quoc77]

I have bubbles all over the back wall of my tank and underneath my crushed coral. My substrate is about 2in. Are these bubbles normal? My tanks has been setup for 8 months now and have never seen anything like this before. Also, I am having alot of brown algae all over my substrate. Could this be the cause of it?

 

[Anonymous]

Check your ntrate level. My guess is that it is high and you are growing algae in quantity now. The bubbles could just be oxygen produced by the algae.