I too have had a small problem with algae this hot season, I did not have it last season. A poacher removed quite a few tilapia fingerling and I stocked a predator that ate the fry. That left me with very few small tilapia. When there were many small tilapia and no predators the 3 to 6" fish could be seen every evening, mouths open feeding at the surface. Mine are nile and I have not had any success with an artifical as yet.