My Aquathol Super K has always knocked out my coontail in 72 hours without issue. I know it's not the same product, but I'm surprised you're not seeing better results. Maybe a fluridone treatment would be the best way to go at this point? I'm not a herbicide expert by a long shot, hopefully someone will be along soon. Sorry CP to hear your pain. FYI - I can't see how the coontail is hurting your fish - they are likely LOVING it I'm sure, but you can't allow it to get out of control obviously - which is why you're trying to treat it.

Many men go fishing all of their lives without knowing that it is not fish they are after. ~ Henry David Thoreau

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