Hydrothol® 191

Hydrothol 191 is a liquid formulation that provides control of both weeds and algae.  Used primarily as an algicide at rates of 0.05-0.3 ppm, it provides excellent control of a broad spectrum of algae including planktonic, filamentous, and branched algae.  Hydrothol 191 also provides control of aquatic vascular plants and can be tank-mixed with Aquathol K to improve the efficacy on difficult-to-control weeds.  Hydrothol 191, works relatively quickly providing algae control in just a few days, and weed control similar to Aquathol K.  There are no restrictions on treated water used for swimming, fishing or irrigation*.

*Read and follow label directions.

Weeds controlled by Hydrothol® 191

All Weeds controlled by this product

Plant & Algae Guide

State Registrations


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