I'll bet that a glyphosate based product that is rated for pond use would get it, but it's also get anything else that it's sprayed on as well. I think a Diquat based product would also work.

It looks like the lily pads are spreading as well. You'll need to keep an eye on them because they can cover a great amount of water, and they are difficult to eradicate as well.


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3/4 to 1 1/4 ac pond LMB, SMB, PS, BG, RES, CC, YP, Bardello BG, (RBT & Blue Tilapia - seasonal).