API Pond Algaefix pond algae treatment 1 gal — copper-free, EPA-registered concentrate for clear water

API POND ALGAEFIX is a copper-free, EPA-registered liquid that quickly controls green water, string, and blanket algae to help restore clear, healthy-looking ponds and fountains.

API has supplied aquatics-care products for nearly six decades, and POND ALGAEFIX is formulated to address common algae outbreaks without harming fish, aquatic plants, or nearby wildlife when used as directed. This one-gallon concentrate treats up to 38,400 gallons and is designed for ponds, koi ponds, and water features that have good aeration and circulation.

How quickly will I see algae reduce after application?

Results are often visible within a few days: floating green water will start to clear and string algae will begin to break down. Continue dosing every three days until the problem is under control, then maintain weekly to deter re-growth.

• Visible improvement commonly within 48–72 hours
• Repeat dosing every three days until clear
• Switch to weekly maintenance doses once algae is controlled

Is this safe for fish, plants, and beneficial bacteria?

API POND ALGAEFIX uses a natural active ingredient in a copper-free formula that’s EPA-registered and formulated to avoid disrupting beneficial pond bacteria or accumulating in sediment when used as directed. Follow label instructions for dosages and ensure adequate aeration for the best safety margin.

• Copper-free — reduced risk to sensitive organisms
• EPA-registered for product reliability and oversight
• Designed not to inhibit helpful bacterial processes in ponds

Which algae types does this control, and where can I use it?

POND ALGAEFIX targets common freshwater algal issues: green water (microscopic plankton), filamentous string or hair algae, and blanket weed in outdoor ponds and decorative fountains. It’s intended for non-saltwater environments and best used with good water movement and aeration.

• Controls green water (Chlorella), string/hair algae (Cladophora), and blanket weed (Oedogonium)
• Suitable for backyard ponds, koi ponds, and ornamental fountains
• Not intended for marine or brackish systems

How do I apply it correctly and what maintenance is required?

Shake or mix the concentrate and distribute evenly across the pond surface, ensuring robust aeration is active during treatment. Repeat doses every three days until algae is resolved; then apply weekly to prevent recurrence and reduce manual cleaning.

• Ensure vigorous aeration and circulation before dosing
• Mix thoroughly and disperse evenly across the water surface
• Follow repeat schedule: every 3 days until controlled, then weekly maintenance

Who is this for: API POND ALGAEFIX is for pond owners, koi keepers, landscape professionals, and anyone who manages outdoor water features and wants an EPA-registered, copper-free option to control common algae. It’s appropriate for hobbyists seeking an effective, maintenance-friendly treatment that preserves fish and plant health when used according to directions.