Cygnet - Copper Sulfate - 50 LB BAG

Cygnet - Copper Sulfate - 50 LB BAG
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Cygnet - Copper Sulfate - 50 LB BAG

SKU: 209
  • This product requires special shipping & handling and will require extra freight charges. Please call (800) 785-3301 for a freight quote.
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  • Made for controlling algal blooms
  • Most basic copper compound that has been used for years as an algaecide

This 99% copper sulfate fine product is for controlling algal blooms, it is the most basic copper compound that has been used for years as an algaecide. It is not very effective in hard water and can be toxic to fish in soft water.

Active Ingredient: Copper Sulfate Pentahydrate

For use on:

  • Lakes
  • Ponds
  • Irrigation Systems

Weeds Controlled

  • Algae
  • Cyanophyceae
  • Diatomacese
  • Protozoa
  • Leafy and Sago Pondweed


How to apply: Rates vary based on water volume and hardness. Use more in hard water and less in soft water.
When using Copper Sulfate to control algae, there are many factors to consider such as water hardness, temperature of the water, type and quantity of vegetation to be controlled and the amount of water flow. Algae can be controlled more easily and effectively if treatment with Copper Sulfate is made soon after plant growth has started. Under such circumstances, small amounts of Copper Sulfate can effectively control algae in water. However, if treatment is delayed until large amounts of algae are present larger quantities of Copper Sulfate will be required. Control of algae in water systems is not always permanent. Usually algae is more difficult to control with Copper Sulfate when water temperatures are low. The dose rates for Copper Sulfate are based on a water of 60 º F or higher. Larger amounts of Copper Sulfate will be required in hard water. Normally, larger quantities of Copper Sulfate will be required to kill algae in water that is flowing than in a body of stagnant water. If possible, curtail the flow of water before treatment and hold dormant for about three days after treatment or until plants have begun to die. When preparing a Copper Sulfate solution in water, it is best that the mixing vessel be made of plastic or glass. It is best to treat algae on calm, sunny days when heavy mats of filamentary algae are most likely to be floating on the surface where it can be sprayed directly. When in doubt about the concentration to be used, it is recommended to start with a lower concentration and gradually increase the concentration until the algae is killed.

See Label for complete application instructions.


This pesticide is toxic to fish and aquatic invertebrates. Water treated with this product may be hazardous to aquatic organisms. Treatment of aquatic weeds and algae can result in oxygen loss from decomposition if dead algae and weeds. This oxygen loss can can cause fish and invertebrate suffocation. To minimize this hazard, do not treat more than 1/2 of the water body to avoid depletion of oxygen due to decaying vegetation. Wait at least 14 days between treatments. Begin treatment along the shore and proceed outwards in bands to allow fish to move into untreated areas.

TERRESTRIAL USES: This pesticide is toxic to fish and aquatic invertebrates and may contaminate water through runoff. This product has a potential for runoff for several months or more after application. Poorly drained soils and soils with shallow water tables are more prone to product runoff that contains this product. Drift and runoff may be hazardous to aquatic organisms adjacent to treated areas. Do not apply directly to water, or to area where surface water is present, or to intertidal areas below the mean high water mark. Do not contaminate water when disposing or equipment wash water or rinsate.

See Label for complete restrictions.

Product Label Download SDS