The Best Pool Algaecide For 2021 – A Product Review

Updated on

Rupam Krishna Bharali

About the author

Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip

As an Amazon Associate I earn from qualifying purchases.

Are you struggling to keep algae out of your pool? A good pool algaecide can reduce the amount of brushing and scrubbing you need to do and will keep you from overusing shock treatments. In this guide, we help you find the best pool algaecide that you can safely combine with your current pool chemical products to boost the efficiency of these products and to help you finally clear up your green pool so you can cool down in crisp clean waters. 

What is Pool Algaecide?

Algaecide is a chemical treatment that is specially developed to prevent algae from growing in your pool. Pools with algae are cleaned by applying chlorine products that will kill these aquatic growths. But it is good to add pool algaecide to your maintenance routine because these algae depressants will keep algae from returning. Algaecides are especially helpful for keeping algae in check during summer since these aquatic plants grow rapidly during the warmer weather months. 

Are There Different Types of Algaecide?

Lots of different companies produce pool algaecides, but there are only three main types of algaecides that you can buy. Here is a quick look at the different types:

Quat Pool Algaecides

Quat pool algaecides contain quaternary ammonium compounds and are a detergent that can kill most algae species. These products will attach to algae cells and will dissolve their protective membrane. Once that protective layer is destroyed, the chlorine can penetrate the algae cell’s core to kill the algae.

This type of algaecide is considered the most economical and you can get them in 10% and 50% concentrations. 

Adding too much quat pool algaecide can result in foaming because it is basically a type of soap but it won[‘t cause straining. 

Polymer or Polyquat Pool Algaecides

Polymer algaecide or polyquat algaecide are variants of the quat compound. But these products have two advantages over other types of algaecide products; It is non-foaming and non-straining which means you don’t run any risks if you add too much product to your pool.

This type of algaecide works the same way as quat pool algaecides. The polymers are designed to attach to negatively charged algae cells and spreads over the algae bloom to smother the growth and eventually the algae cells. 

Polymer algaecides are twice as effective and last longer than quat algaecides but they can be expensive. They are usually available in 30% or 60% concentrations. 

Metallic Pool Algaecides

Metallic pool algaecides are copper-based products with positively charged ions. Copper naturally kills bacteria and other growths on contact. 

Algae cells are negatively charged. By introducing positively charged metal ions (metallic algaecides) into the water, these ions will attack the outer walls of the algae particles. The metallic compounds will poison the algae cell nucleus to kill the infestation. 

Metallic pool algaecides are great for treating an active algae problem and can be helpful for treating bacterium like pink algae or black algae. But you should never over-use this treatment since algae can become resistant to these products which can make them ineffective in the future. 

Do I Use Shock or Algaecide First?

You should shock your pool before adding an algaecide treatment because this product will support the chlorine and boost your chances of killing all algae particles. 

A proper pool shock treatment should be used which can increase hour chlorine levels to 12ppm. Once these levels return to normal levels of 1 – 3 ppm, you can add the correct amount of algaecide to several areas in the pool while the pump is running. 

This routine is most effective for killing algae and keeping new growths from forming. It will also speed up your pool cleaning process so you can enjoy crisp clean water in no time at all. 

How Often Should I Use Pool Algaecide?

This might depend on the type of alga infestation you have. 

Black algae can easily be killed by metallic pool algaecides but it can become resistant to these chemicals if you overuse them. Ideally, you should only use metallic pool algaecides once to kill and remove black algae from your pool. You can do this every couple of months if you get a breakout.

Other types of algaecides like quat or polymer algaecide treatments can be added to your pool on weekly basis. These algaecides act as a backup for your routine sanitation program and will keep algae from growing in your pool, to begin with. 

It is important to follow instructions carefully when you are adding algaecide treatments (especially with a quat algaecide) or you can experience negative effects like foaming or straining. The amount of algaecide per gallon of water differs for different products. 

What Best Pool Algaecide For My Pool?

Now that you understand the different types of pool algaecides and the importance of these pool chemicals, it is time to have a look at some of the top products to use for your pool. Here is a quick guide and product review on the best algaecide treatments to get if you want to keep algae out of your pool. 

HTH Super Algae Guard

This algaecide by HTH is our top pick because it has thousands of positive buyer ratings. Thousands of people tried and trust this product and found it helpful for keeping their pools from turning green.

The algaecide is practical for any type of pool and pool filter and it can be used to treat green, black, and mustard algae. It is a concentrated formula that will last you a long time since you only need to add 0.1 fl. ounce per 1000 gallons of water once every three to five days. 

This pool product is loved by families because you can swim just 15 minutes after adding the product to your pool. It won’t interrupt any of the fun but don’t overuse the algaecide since it may cause frothing or foam if you add too much. 


Qty – 1 Quart bottle

Pool compatibility – Any type of pool (Vinyl, concrete, salt, or chlorine)

Algae species – Green, black, and mustard algae

Dosage – 0.1 fl. oz per 1,000 gallons of pool water

Recommended routine – Every 3 – 5 days

Swim safety – Swim 15 minutes after use


  •  Compatible with all pool types including vinyl-lined pools
  • Treats all common types of algae
  • Ideal for regular routine use
  • You can safely swim 15 minutes after adding the product
  • Affordable price range
  • Helpful as a clarifier


  • Can foam if you add too much product 
  • Manual weekly application required

Pool RX 6 Month Algaecide 

Pool owners who don’t have a lot of time on their hands can use this algaecide by Pool RX. This product is very convenient since it will keep your pool clear from algae for up to six months and you only have to add one pod to your pool filter one time. 

This algaecide is practical for larger pools of 20 – 30 thousand gallons. You can add more pods for larger pools and the algaecide won’t affect your pH levels at all. It might cause a spike in copper sulfate levels and could discolor copper hair green due to the metallic composition of the product. 

But it is a great product to trust if you want to kill all types of algae and keep a clean pool without working too hard on maintenance. 


Qty – 1 Piece unit

Pool compatibility – Any pool type over 20k gallons

Algae species – All types of algae

Dosage – 1 pod per 20 – 30 thousand gallons of water

Recommended routine – One pod every 6 months

Swim safety – You can safely swim right after installing the pod


  • One of these products will last 6 months
  • It will kill all types of algae
  • Reduces the number of chemicals you need for keeping your pool clean
  • Very easy to use since daily application isn’t needed
  • Chelated minerals naturally fight off bacteria and algae
  • Good value for money
  • Suitable for any type of pool


  •  The product can increase your pool copper levels
  • Not ideal for tiny pools

SeaKlear 90-Day Algae Prevention and Remover

This popular algaecide by SeaKlear is a great treatment to use if you want to clear up a green pool. The pool chemical can be used to kill and remove all types of algae including black algae and will keep algae from resurfacing for up to 90 days as long as you properly maintain your pool after adding the treatment.

This low-maintenance treatment is suitable for all pool types and you can swim in your pool one day after using the product. It is a perfect algaecide for people who don’t have the time to add pool chemicals every day. 


Qty – 1 Quart

Pool compatibility – Any type including saltwater pools

Algae species – Blue, green, black, and yellow algae

Dosage – 1 every 90 days

Recommended routine – 1 Treatment every 90 days (for closed pools)

Swim safety – Swim one day after pool treatment


  • Non-foaming and non-straining
  • Useful for all algae species including black algae
  • Long-lasting effects
  • Can be used along with other pool products like chlorine or borax
  • Lots of positive buyer ratings
  • Easy and simple to use


  • Contains copper metals
  • Bad black algae treatments might require additional products

Kem-Tek 60% Algaecide Concentrate 

The algaecide by Kem-Tek is helpful for killing any type of algae and it is mild and safe enough to use in any type of pool. You need to apply the treatment every week to keep algae from growing in your pool water. The product doubles as a water clarifier since it can help clear up green or milky-looking water.

The polyquat treatment is very easy to use and doesn’t introduce too much copper into the water which will keep light-colored hair from turning green. 


Qty – 1 Quart

Pool compatibility – All pool and filter types

Algae species – All types

Recommended routine – Every week

Swim safety – Safe for swimming


  • Affordable price range
  • Safe for sensitive filtration systems
  • Can be used to treat algae breakouts
  • Can help prevent algae growth
  • Long-lasting effects
  • Effective results within one day
  • The poly quat formula does not foam or strain


  • Won’t kill algae alone. Proper chlorine levels and brushing is also needed
  • Weekly maintenance is required to keep pool clear

BioGuard Algae All 60

The non-foaming algaecide by BioGuard is a very safe product to use since you can apply it to any type of pool including those with added fixtures like fountains. This algaecide only needs to be added once a week and it will kill all types of algae species in your pool. The non-foaming formula is also suitable for indoor or outdoor fountains which makes it a practical product for people with multiple water features. 


Qty – 1 Quart

Pool compatibility – Chlorine or brominated pools of any kind and fountains

Algae species – All types of algae

Recommended routine – Once a week


  • Suitable for any type of pool
  • Effective killer for all algae types
  • Non-foaming formula
  • Also kills white mold
  • Low copper levels won’t discolor children’s hair 
  • Perfect for pools with attachment spots like fountains


  • Can cause staining
  • Scrubbing and adequate pH levels are still required

Final Thoughts

We do hope that this guide helped you find the best pool algaecide so you can keep those icky green growths out of your pool. If you are also looking for other great advice on the best ways to get rid of black algae, green algae, or pink algae slime then you should have a look at our other guides. On Algalweb, we share the best tips to help you clear out any type of algae breakout in any type of pool so you can enjoy a crisp and clean pool all year long.

Amazon and the Amazon logo are trademarks of, Inc, or its affiliates

Leave a Comment