anthonyk,
Haven't had time to read each response so mine has probably already been covered...but my suggestion is to stock 1 grass carp in your pond. Unfortunately, you will have to apply for a permit from T,P,&W. One will do you a good job for about 3 to 5 years when you will need to replace it with another one. If you develop severe algae problems consider also stocking a few Tilapia (Mozambique)...no permit required. They will die off each winter when the temps fall below 55 degs, but will provide excellent natural algae control in most ponds during the summer growing season.