My experience with Aquathol liquid is about the same as Diquat. Aquathol is a little more expensive, but it works well. Also, I've lost fish with Hydrothol, but they were buried in the weeds I was treating. Fish that were roaming were fine. Depending on what the weeds are, Navigate is a 2 4-D granular that works well also.
What weeds are you targeting?
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