I have a 1 acre pond located in Southern Wisconsin. The pond depth varies from 12' to 2' having an irregular bottom with average depth probally 5-6 feet. The pond was constructed 2 years ago. The pond is quite clear being spring fed and has a 30 to 40 gal/min outflow. The pond receives no agricultural runoff and native oak woods are located above the pond which is then buffered by grass. The pond is stocked with bluegills, bass and a few catfish. Plant growth has been quite slow to establish itself it seems. Last summer we introduced some native plant species, Chara, Large Leaved Pondweed, White Water Lily to compliment the Pondweed and Chara that was beginning to establish itself. The pond is aereated with a windmill aereator. As the water began to warm last year we began to have some significant algae blooms appear. The surface would at times be covered with globs, although on windy days these would be isolated to the opposite shore. In addition the algae seemed to blanket the submerged vegetation and hamper its growth if not kill it. As the water cooled this fall the growth subsided but still was somewhat evident. There is still some growth this winter that can be seen through the ice. The algae growth hampers fishing and swimming.

I am interested in any ideas about controlling these algae blooms. Will they subside as the submergent vegetation more completely establishes itself? Are there any non chemical treatment alternatives? Does the ph of the water make a difference and if so can it be altered to help without harming the pond otherwise? I know chemical treatment would help but I don't know the long terms effects on the pond - maybe it would help the submergent species establish themselves which would in turn help minimize the blooms. I am not necessarily looking for a quick fix and would be interested in experimenting with anything short of chemical treatment if there is a possibility of something being effective. I am not against chemical treatment however if it is the only way to get the problem under control.

THOMAS R. NESHEK