Whats this?

Just started seeing this in my pond late last year following the low water conditions and the drought.

I forget the name but I have sprayed and killed mine with an aquatic approved spray. A systemic spray, along the lines of roundup but aquatic approved. I bought it at a local feed store.

http://aquaplant.tamu.edu/database/submerged_plants/american_pondweed.htm

I dont think it's that. These leaves are very small.

I think it's a relative tho. Maybe it's Potamogeton diversifolius.

http://aquat1.ifas.ufl.edu/potdiv.html

aka variable leaf pondweed or waterthread pondweed?
http://plants.usda.gov/java/profile?symbol=PODI
http://plants.usda.gov/java/county?state_name=Indiana&statefips=18&symbol=PODI