Brown mold and Bubbles

[magicrub]

I have 55 gal aquarium, it has been running for over a month. The aquarium used to be pull of corals like mushrooms that came with the live rocks when I bought it. I went for a month vacation and when I get back everything is dead, my sister unplugged the filter accidentally. I set it up again using the old rocks and sand. The tank have 3 small fish that seemed to be happy and well. I will put some nice corals soon. I just noticed today that lots of brown mold with bubbles appeared at the bottom of the tank on the rocks and sand. I was just wondering if something is wrong, or is it just normal at the beginning month to have those brown mold. If this is not normal what will I do? Please advise

 

[duke62]

its called cyano bacteria,you have to much phosphates in your tank.there is a thread about it here.read it it works

 

[CHEMCHEF]

Your tank is clycling agian,,due to die off from the filter being unplugged. IMO
How long was it unplugged for.

 

[LongIslandAndy]

When things die like that, the tank has an excess of nutrients and you will start to cycle again. I would start doing 20% water changes every few days, sysphon out what blown stuff that you can and WHEN THE WATER IS STABLE add a clean-up crew. Mexican turbos eat a lot of junk. I would use about 4 in a 55

Good luck