My next step is to try and clear the FA out manually. Does anyone have any tried and true methods ? I also plan on using the dye to treat the water and keep the sunlight from filtering down to promote new growth.

I realize this will be a long-term battle that I will have to fight, but I would prefer my pond (lake) be aesthetically pleasing.

I live i Illinois, so there are some restrictions about introducing Tilapia (This state loses permits and fees). But I am concerned about introducing an invasive species into the water. To the best of my knowledge I have catfish, bass and turtles...... LOT's of Freakin' Turtles. Any idea on what I can expect in terms of affect on them ?

I probably should have mentioned that the pond varies in depth, from several inches at the extreme edges to an alleged depth of 25' at the bottom. That being said, it is an old pond, probably 30-40 years and I am sure there has been a loss due to organic build-up. Right now I wouldn't dive down to check the bed, as visability is probably like the East River (NYC) in the 70's!!