Q:[ Water Hyacinth]

 I have run a little experiment. I placed some water hyacinth and water   
lettuce in a small pond in my back yard.( I plan to get to the point and   
to planted tanks after some background info ). The water in the pond was   
dark and hand a green tint to it. After 2 weeks it is now clear and   
clean.  I have no filter in the pond and it is located in full sun. What   
I'm wondering about, and thinking of trying, is to use water hyacinth in   
my indoor tank to help control alge. So, before I reinvent the wheel, I   
thought I would ask if anyone out there has already tried this.
      Thanks in advance,
       Larry Beach