The secret to growing massive amounts of algae is fertilizer. It's also the easiest thing to get into trouble with. Putting in the right amount of fertilizer is the hardest thing I have yet to learn. I nearly killed all of my fish one time doing it but I think I'm catching on. It's a good thing I had all the free time on my hands when I first started out. I'm absolutely sure that if I did not have all the aquarium experience and free time to watch them, that I would have killed these fish ten times over!