If your identification is correct (any or all of the 3 listed) Reward works on all of them.

If you can get one or two strands of the weed, place it on a white background (paper plate or copy paper) and take a close up clear picture of the plant, it might help narrow it down easier.

www.hoosierpondpros.com

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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).