It depends on the type of "weeds". Some "weeds' are actually algae (Chara).

If you can ID the weed I'm sure we can give you options.

As for not harming the fish, that really is up to the person applying the chemical. Don't read the label for proper application? Possible fish kill. All the herbicides/algaecides that people in the know here on the forum recommend are approved for use in ponds and safe for the fish.


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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).