API Pond Algaefix Algae Control Solution, 16-fl oz bottle

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About This Item

Details

  • Effectively controls green water algae, string or hair algae and blanketweed in ornamental ponds.
  • Helps keep ponds, water gardens and ponds clean and clear.
  • Algaecide controls existing algae and helps resolve additional algae blooms.
  • This algae solution is safe for live plants and pond fish.
  • Do not use with freshwater crustaceans, including shrimp, crabs and lobsters.

Instructions

FAQ

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Special Note
  • 8-oz bottle treats up to 2400 gallons.
  • 16-oz bottle treats up to 4800 gallons.
  • 32-oz bottle treats up to 9600 gallons.
  • 64-oz bottle treats up to 19,200 gallons.
  • 1-gallon bottle treats up to 38,400 gallons.
  • 2.5-gallon bottle treats up to 96000 gallons.

About API Pond Algaefix

Why Use API POND ALGAEFIX Algae Control?

Algae growth can appear as “green water” blooms, “pea-green soup”, filamentous algae on plants, or as floating mats known as blanket weed. Algae grows when there are excess nutrients in the water—usually in spring prior to plant growth or during summer in direct sun. API POND ALGAEFIX Algae Control works quickly to control algae growth and keep ponds, water gardens and fountains clean and clear.

Controls Most Types of Algae

Before Using

Make sure your pond has vigorous aeration to avoid fish loss due to low oxygen levels. When algae is controlled and removed by the filter or settles to the bottom of the pond, oxygen may drop to harmful levels without adequate aeration. Pond water also carries much less oxygen in warm weather.

Algae Types

API POND ALGAEFIX helps control three main types of algae:

1.    Green Water Algae (Chlorella)

2.    String or Hair Algae (Cladophora)

3.    Blanket Weed (Oedogonium)

How to Use API POND ALGAEFIX Algae Control

Treating your pond to control algae is simple. For best results, be sure to read and follow all label directions.

Step 1

Vigorous 24-hour aeration is required during treatment. Do not shut off pond pumps or aeration devices at night.

Step 2

Remove as much algae as you can by hand before treating your pond.

Step 3

Disperse API POND ALGAEFIX evenly around the pond and thoroughly mix it into the water. DO NOT OVERDOSE.

Step 4

As algae dies off, remove as much of the dying algae as possible.

Calculate Pond Volume Before Use

To ensure accurate dosing, determine your pond’s volume and then use the dosing chart to figure out how much API POND ALGAEFIX to use. For square and rectangular ponds: avg. length (feet) x avg. width (feet) x avg. depth (feet) = cubic feet of water. Cubic feet of water x 7.5 = volume in U.S. gallons. For round ponds: top diameter (feet) x bottom diameter (feet) x height (feet) x 0.785 x 7.5 = volume in gallons.

About API

The team at API has a passion for fish and understands the rewards and relaxation fishkeeping can bring. For almost 60 years, they have developed premium products with a focus on proven and effective results. API offers a range of testing kits, water conditioners and nutritionally superior fish foods. They are dedicated to making a better underwater world for the benefit of fish and those who keep them.

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Questions & Answers

12 Customer Questions

Hello! Should AlgaeFix and the sludge remover (EcoFix, I believe) be used at the same time, or should the sludge remover be added after all the Algaefix treatments are completed? Thank you!

Answer by Chewy • Apr 20, 2018
It is best to use this supplement on it's own until the algae is controlled.

CAN I USE THIS ON MY INDOOR KOI TANK, 120 GALLON?

Answer by Chewy • May 01, 2021
This solution is designed to be used on ponds, water gardens and fountains.

What is the shelf life of this product?

Answer by Chewy • Jul 06, 2020
API Pond Algaefix Algae Control Solution does not expire. The shelf life is indefinite.

Is this algiecide harmful to birds if used in a fountain birdbath?

Answer by Chewy • Jun 07, 2021
This solution will not harm fish or plants. It is hazardous to humans and domestic animals if swallowed or absorbed through the skin.
Reviews
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4.4
Rated 4.4 out of 5 stars
433 Ratings
Terms & Conditions

199 Customer Reviews

Rated 1 out of 5 stars
By Patrick on Jan 16, 2026

False advertising

This bottle os algaefix is really for a pond. They are in a similar category, so a lot of people bye it for there fish tank. The problem with that is this product

This bottle os algaefix is really for a pond. They are in a similar category, so a lot of people bye it for there fish tank. The problem with that is this product will kill your fish.

Rated 5 out of 5 stars
By Debbie on May 12, 2025

Destroyed Algae in less than 24 hours

Wow. I was having a real problem in my pond for almost a week until I read the side of my API Pond Ecofix Sludge Destroyer and it said if the problem is bad, first

Wow. I was having a real problem in my pond for almost a week until I read the side of my API Pond Ecofix Sludge Destroyer and it said if the problem is bad, first use API Pond Algaefix Algae Control Solution. I ordered it and it doesn't take much for the size pond I have. I added it and the next day my pond was clear. The second day, I could see every acorn and leaf on the pond bottom. A few days later, there was a small amount of green floating on top, so I treated it again and now, the water is clear as a bell. This works wonderfully.

Rated 5 out of 5 stars
By Janna on Sep 15, 2025

It works!

Delivered promptly and solved the ugly algae problem. Too soon to see how long it lasts.

Delivered promptly and solved the ugly algae problem. Too soon to see how long it lasts.

Rated 2 out of 5 stars
By janice on Nov 24, 2025

Pond water treatment

I really want it for my aquarium mom mistake

I really want it for my aquarium mom mistake

Rated 5 out of 5 stars
By Michael on Jun 23, 2025

It works!

Algae started to die off, losing its color gradually fading to a very light tan almost white, during which time I had to remove the dead algae from the pond and

Algae started to die off, losing its color gradually fading to a very light tan almost white, during which time I had to remove the dead algae from the pond and filter almost daily. Just mind the dosage.

Rated 5 out of 5 stars
By Carol on Jul 27, 2025

GREAT PRODUCT

Works great at controlling algae. Price was good. Shipped in a plastic zip lock bag in case there was a leak.

Works great at controlling algae. Price was good. Shipped in a plastic zip lock bag in case there was a leak.

Rated 5 out of 5 stars
By Bette on Aug 18, 2025

The professionalism and quick mail order time

It’s an algae side for my fish. When they start talking to me I will ask them

It’s an algae side for my fish. When they start talking to me I will ask them

Rated 5 out of 5 stars
By Joe on Jul 30, 2025

Easy to Administer

A real no- brainer for our Koi Pond. Controls algae on rocks in steam and falls.

A real no- brainer for our Koi Pond. Controls algae on rocks in steam and falls.

Rated 5 out of 5 stars
By John on Aug 24, 2025

Pond help

Shipment was fast and well packaged. Product works fast. Thanks

Shipment was fast and well packaged. Product works fast. Thanks

Rated 5 out of 5 stars
By Barbara on May 19, 2025

The service

I needed it so bad that the local shop wasn't able to get it to me for 7 days and you delivered it in 2. Thank you so much. That I put you on a standing order.

I needed it so bad that the local shop wasn't able to get it to me for 7 days and you delivered it in 2. Thank you so much. That I put you on a standing order.