I have two ponds that have this growing in them. This is the first time I've had this problem. One pond is stocked with Bass, Crappie and perch and is about 40 years old. The other pond is about 20 years old and is stocked with Hybrid Catfish and Channel Cats. Need to find out what it and how to control it. It seems to grow in swallower water. I see it from the bank to no more than 10 to 15 feet in both ponds. It started out submerged but has grown and is now on the surface of the ponds around the edges. Any idea's on what it is a how to kill it without hurting the fish?? Please see the attached pictures.

Thanks.

Can you take more pics? A better close-up.