This may be acardinal sin.. I am no expert on planted aquariums.
However i found an INSTANT cure for green water.
Any water clarifying agent.. such as Acurel F, when used as directed, will quickly clump up the algae, wich will then be sucked into your filter.
A few hours later you can clean your filter, and poof, problem solved.
If there is anything wrong with this approach, I'd like to know, because it worked wonders for me, didn't kill any fish, and a month later the plants are still doing well....
The green water never came back either...
Now if i could ust figure out how to get rid of this brown algae!!!