Pond Boss Forums AQUATIC VEGETATION Controlling unwanted plants Homemade weed killer. Pond safe??

Correct statement, in reference to terrestrial-labeled glyphosates which contain tallow-amine surfactants (wetting-agents) which can be harmful to aquatic organisms - including fish.
If a non-selective herbicide is appropriate, use an aquatic-label formulation of glyphosate (ie. RODEO, ROUNDUP CUSTOM, AQUANEAT, SHORECLEAR, etc.), OR imazapyr (POLARIS, etc); all of which will require an additional surfactant to enhance leaf-coverage and leaf-cuticle absorption.
If a selective herbicide treatment is desired (to control broadleaf weeds and woody plant species while leaving grassy-plants mostly unaffected), consider using an aquatic-labeled 2,4-D or triclopyr product, OR a soon-to-be aquatic-labeled formulation of aminopyralid. More details on the later in June.
For anyone interested in managing wildlife food plots, there are also grass-selective herbicides that control undesirable & intrusive grasses while leaving broadleaf plants/dicots unaffected.