My live sand keeps turning kind of brown all over the place IÃ¢â‚¬â„¢m not sure if its algae, I have no clue what to do about it or how to get rid of it. I have a 55 gallon tank set up for saltwater; my aquarium has been running for about 6 weeks. I have 4 fish two clown fishes and two blue damsels. I have two filters a mechanical and biological one, I just recently did water changed, I feed my fish once a day. I also have 6 Ã‚Â½ pounds of live rock in it.