I've been fighting a massive algea bloom in my freshwater 40 gallon aquarium for a year and a half in a tank I've had running for 15 years. I used chemicals, I changed the water, changed the gravel, killed the fish, restarted, changed the filter system and the damned stuff kept coming back.

Finally, I recall that sometime ago I had changed the light!!!! Changed the bulb again and all is now calm and peaceful. Seems it had a bulb for aquariums plants, and man o man did it grow the algae. There's a tip for any freshwater aquarium buffs.

I keep half the lights on my 75 gallon aquarium shut off.

My wife and I keep freshwater planted aquariums... one of the key steps to doing so is to plant a BUNCH of plants during the initial set up... that way they absorb the nutrients in the water before algae can gain the advantage...

Lots of cool planted tank photos here:

http://www.plantedtank.net/forums/pGallery.php

Nice!

I was gonna suggest what you already posted. Sitting close to a window or door can do the same thing.

I have some friends who solved their algae problem by leaving the tank empty and and using thin fishing line to hang very lifelike plastic fish in it. Unless you notice that they don't move, it looks very real, much better than it sounds.

Only way to kill it all period is to black the tank out for a week or 2. Cover so absolutely no light gets to it. Algae is a plant and plants die with no sunlight. It's the only guaranteed method. My father and I used to be huge into freshwater aquariums. Please don't go crazy with chemicals it's super hard on the fish. Also the light is a huge factor too. it's been awhile since i looked but there are many many types of bulbs and u may have one that promotes plant life.


Good guide for lighting:

http://www.drsfostersmith.com/pic/article.cfm?articleid=414


How to black your tank out:

http://www.aquariacentral.com/forums/threads/how-to-properly-black-out-a-tank.213369/

Thanks for the links. Good stuff.

I changed the water and the bulb three weeks ago and all is good. Really drove me crazy for a while. I blacked out the tank for a week and as soon as I uncovered it -boom!