The first one is some kind of Potomogeton species for sure. Most likely Sago. Algae? No way Walt!

What kind of pondweed it is, is irrelavent to grass carp. Correct me if I'm wrong but grass carp pretty much like all the pondweed species don't they?

So I would feel safe with grass carp as a biological control.

If pigs could fly bacon would be harder to come by and there would be a lot of damaged trees.