Crystal Blue Copper Sulfate Algaecide – 5 lb Granular Algae Control for Large Ponds

Crystal Blue Copper Sulfate Algaecide is a granular copper sulfate pentahydrate designed for larger water bodies. This 99 percent pure granule targets actively growing algae and helps manage filamentous and string algae in ponds, lakes, or other large waters.

What to expect

The granular formulation enables targeted action on thick algae mats while allowing you to monitor overall water health during treatment. Results may vary with conditions and timing.

Key considerations

• Use on actively growing algae when water temperature is above 60F (15.6C).
• Best applied on top of dense mats; avoid treating too large an area at once to protect oxygen levels for fish.
• 5 lb bag of granular copper sulfate is intended for large bodies of water, not small decorative ponds, water features, or pools.
• Do not use in water containing koi, goldfish, trout, or grass carp.

What you get and how to use it safely

• 5 lb granular copper sulfate pentahydrate for pond algae control.
• Clear guidance on application with attention to fish safety and water conditions.

Crystal Blue aims to support responsible algae management in larger water systems while prioritizing ecosystem balance and user safety. Follow local regulations and test water conditions when applying.