I've got a bad problem witha green algae covering all my rocks in my tank. I've recently set it up and after adding fish last week there is now green algae coverong my tuffa rocks. It looks horrid as my rocks are white. I've cleaned them with a stiff brush but i want to know how i can stop it coming back. When i had the tank set up as a comunity tank i never had this problem, but I did have a 8 inch common plec who must of ate it all?