One of the experts will be along to help you shortly, here is my $.02 while you wait. Depending on your budget and how quickly you want to see results, dredging/excavating to remove the nutrient rich "muck" at the bottom of your pond will provide the most immediate and most significant solution. If I were in your shoes, I would excavate and then add bottom aeration set up and stock some grass carp. Grass carp do a very good job at keeping plant life in check. They will likely not have a significant impact on your FA as long as there is a good supply of submerged vegetation, but they will help. Stocked in high enough numbers, they will basically wipe out submerged vegetation. This can be detrimental to your other fish populations, but if fishing is not a priority it may be something to consider.