This film did not show up until the pond bloomed, on a five acre pond I put 3 bags on a rack and scattered 4 bags around the shore edge. The directions said to use 1-2 bags per acre so I decided on using 7. The water clearity was at 22 inches and went to 14 on the side of the pond the wind was blowing from, but with the film forming on the other side the clearity is about 4-5 inches at the most. The film covers about 1/8 of the pond. I live in Georgia and the management book says to fertilize when clearity is over 18 inches and try to maintain bloom for 12 to 18 inches for this area. With all the rain this year and the red clay in this area it took a while for the pond to clear this year. The film that is forming is a light green and looks kinda like a food coloring. No problems with weeds. Thanks for any comments.