Kelly I am a strong proponent of tilapia because they do two things for me. One they remove almost all of the filamentous algae and two they feed my predators. I spend about a hundred dollars a year stocking the tilapia and once stocked there is no monitoring or waiting for the right time to apply chemical. I have a very fertile pond. I fertilize the pond and the pasture around it and without the tilapia I would have a very unfishable pond. The pounds of tilapia per acre, just like the fertilizer, is less than the reccomended value. I have found for me that stocking four pounds of tilapia per acre is optimum. It may be different for you but I have been doing it now for four years. When I stocked ten pounds per acre they removed all plantlife from the pond and not just the filamentous algae. Stocking four pounds per acre still leaves many of the other plants after removing the filamentous algae.