Description
- Description
- Specs
Hydrothol 191 is a liquid aquatic algaecide and herbicide for control of algae and aquatic plants in quiescent, slow-moving, and flowing water sites. It is especially useful for planktonic, filamentous, and branched algae, with typical algae rates from 0.05 to 0.3 ppm endothall acid and higher rates available where longer control or tougher species require it.
Hydrothol 191 also controls submerged aquatic weeds such as hydrilla, pondweed, coontail, milfoil, naiad, sago pondweed, and other labeled aquatic plants. It may be sprayed on the water surface, injected below the surface, or applied through drip or metering systems in flowing water. Always read and follow the label before use.
Features and Benefits
- Liquid aquatic algaecide and herbicide for professional water management
- Controls planktonic, filamentous, and branched algae
- Provides control of labeled submerged aquatic plants
- Works quickly, with visible algae control usually observed in a few days
- Can be applied as a surface spray, subsurface injection, or metered flowing-water treatment
- Can be tank-mixed with Aquathol K where labeled to improve difficult aquatic weed control
- Useful in lakes, ponds, slow-moving water, and certain flowing-water applications
Use Sites
- Lakes
- Ponds
- Quiescent water bodies
- Slow-moving water
- Flowing water, excluding irrigation canals where restricted by label directions
Target Weeds and Algae
- Planktonic algae
- Filamentous algae
- Branched algae
- Floating algae mats
- Hydrilla
- Coontail
- Milfoil
- Naiad
- Pondweed species
- Sago pondweed
- Elodea
- Eelgrass
- Water stargrass
Application Notes
- Algae control: generally 0.05–0.3 ppm endothall acid, or 0.6–3.6 pints per acre-foot.
- Floating algae mats: use a 3–5% spray solution with a minimum of 0.5 gallon per surface acre.
- Submerged aquatic plants: 1–5 ppm, or 1.4–6.8 gallons per acre-foot.
- Apply when algae and aquatic plants are actively growing.
- Do not use in waters containing koi or hybrid goldfish.
- Do not use in brackish or saltwater.
- Fish may be killed by dosages over 0.3 ppm; higher-rate applications should be made as marginal or sectional treatments.
Product Information
- Active Ingredient: Mono(N,N-dimethylalkylamine) salt of endothall – 53.0%
- Acid Equivalent: 23.36% endothall acid
- Formulation: Liquid concentrate
- EPA Reg. No.: 70506-175
- Signal Word: Danger
- Manufacturer: United Phosphorus, Inc. / UPL
| MANUFACTURER | United Phosphorus |
| EPA REGISTRATION | 70506-175 |
| COMPARABLE PRODUCTS | Shaolin Flo 191 |
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