amounts of air into my 55 gallon tank (40 gallons of water) and noticed a huge increase in brown algae (I assume) along the tubing running from the XP3 to and back. I also added river rocks bought from Home Depot recently (washed and cleaned under hot water) to the tank. I can only assume that the brown algae came from the increase in air levels as before I had nothing pumping air into the water. Is there anyway of getting rid of the brown algae?
The algae doesn't grown inside the tank, only on the tubing. Tank consists of 2 RES + 15~ guppies they don't eat.
The water is clear and there isn't any growth on rocks, etc. Any ideas? Thanks. 
