Hi everybody, I've been a silent reader of this wonderful site, but now I feel obligated to share my thoughts about algae. It became a real problem for the last two week. I have a 55 gal tank with 20 blue neons, 2 mollies and 2 platies (had 3 guppies, but they died). I started this tank approx. 4 months ago. I am fascinated with water plants and I see my fish tank as a green water garden mostly, where the fish is just a secondary part of the garden. Unfortunately I have a really bad experience from the very beginning. First, I had a wrong light, probably around 50W, so nothing grew in it, plants remained dormant, then I purchased a nice light with two fluorescent bulbs, 65W each. You can't imagine what a beautiful tank it was for a month or so...Plants were thriving, until a month ago I did noticed some green discoloration of water... Well, my bad, but I thought it would go away by itself... the longer one waits the worth it becomes. I did black out for a 2 days and the water have cleared out to certain extend. But then it turned worth. Now I have it so bad, that you can barely see fish in it. Typical story ( I have read a lot similar stories all over the internet). Well, water has been tested all that time and never showed any signs of disbalance. I mean everything was normal ( that what I've been told at the fish store). I did regular weekly 10-15% water changes, but it didn't work. The last time I was there I specifically asked to test phosphates. It showed the worth possible level on that scale.They said it's because of algae. Well, during this period I've tried 2 different algae destroyers, which didn't help, but 2 fishes died. I guess it had something to do with those chemicals ( I guess those chemicals damage gills), or may be oxygen deprived during the night hours ( how stupid of me was to forget to put the pump on). Well, after reading all sort of forums, I bought a Magnum 350 and left it pumping for the entire night. It did nothing. Then I bought a diatom powder. First portion helped somehow, you could see the fish. After pumping the water for 4 hours, I realized I have to recharge the powder, so I took a new micron filter, added diatom powder and the water cleared even more, but not completely. It still keeps pumping, so tomorrow I will see how it goes ( the fish tank is in the office where I work). What else? Yes, I do realize that I have too much light, because besides of light fixture in my fish tank, I have additional day light from the window and a day light from the fluorescent bulbs in the office. I have to balance it as well. But, my biggest disappointment, is that my real water plants are doing really badly. Leaves are discolored, some got rotten... it looks horrible. I was trying to dig some information if algae bloom can bring damage to the water plants and frankly was not able to find anything about that. Any suggestions? Oh, I think I got this green water problem after adding some fertilizer from the fish store. I do not exactly remember the brand, but I think it was Tetra brand. The guy that initially set up my fish tank, put some strange type of substrate in the fish tank. Again I do not remember the name, but it is a painted stuff, stones are mixed: blue and yellow (some sort of epoxy covered stuff, they actually say it is ok for plants and roots, but I have certain doubts about that)..... Well, sorry for such a long input, but may be it eventually might be helpful to other people who suffer from the same stupid algae blooms.