Your pool’s water has a complex chemical composition that has to be maintained at all times to keep the pool safe to swim in, and algaecide is an important part of that chemistry. Even though chlorine does inhibit the growth of algae to an extent, it can’t do the entire job by itself. That’s because temperature, sunlight, and the mineral composition of the water can actually encourage algae growth, making algaecide an important weapon in anyone’s pool cleaning arsenal.

Unfortunately, it isn’t easy finding the best pool algaecides. That’s because there are dozens of different brands manufacturing this product and not surprisingly, they all claim to have the best product. To slice right through this confusion, we’ve done our own research to find the 10 best products that currently exist. Anyone of the following products is designed to destroy pool algae and keep it out of your pool for good.

Best Pool Algaecides

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10Pool RX Black Unit Algaecide


This Pool RX Black Unit is suitable for use in pools 20,000 to 30,000 gallons in size and is designed to be used as a set and forget algaecide that keeps the water stable for up to 6-months at a time. That’s because it’s made with a blend of minerals that continues to kill algae all throughout its active service life. This unit is dropped into a skimmer or pump basket and works continuously. As the water is recirculated throughout the pool, this minerals in this model will continue to rejuvenate and create an active barrier that prevents new algae from developing.

9In The Swim Super Algaecide


This product is not only designed to be an effective part of any algae maintenance program, but it’s also designed to efficiently kill even the most stubborn algae problems. It’s manufactured with a formulation of 23.5% Copper Triethanolamine Complex and is a non-foaming formula. Only 2-ounces of this product is needed per 10,000 gallons of pool water, and once the pool has been treated, swimmers can swim in it almost immediately. Regardless of whether the pool owner is looking to destroy mustard, blue-green, pink, or yellow algae, this product is up to the job at hand and will effectively deal with it.

8In The Swim 60-Plus Algaecide


Algaecide 60 Plus is a high-quality formula that’s designed to be used with a shock treatment to keep a pool’s chemistry in proper order. This product is designed to kill a variety of different algae types and is capable of dealing with black, pink, and green algae equally well. For an initial dosage, it’s recommended that pool owners use 11-ounces of this product per 10,000 gallons. Fortunately, the maintenance dosage is much smaller, and only 4-ounces of this product is needed for every 10,000 gallons of pool water. It’s also a non-metallic formula and is not affected by the water’s pH level.

7Kem-Tek Pool & Spa Concentrated Algaecide


Capable of being used with both saltwater and freshwater pools and with all different filter types, this pool algaecide can be used by just about any pool owner. This is a non-foaming product that is a 60% concentrate and can be used not only for the treatment of current algae problems but also as part of a regular maintenance routine. It’s designed to destroy many different algae types and to be easily used by the consumer. When used according to directions, and as part of a balanced pool treatment regimen, this product is also able to clarify the water so that it is not only clean but looks clean, too.

6GLB Pool & Spa Products Strike Out


This formula is a triple, chelated copper algaecide that’s designed to effectively get rid of a variety of different algae types. This formula is most effective against green and mustard algae, but can also be used against blue-green algae blooms as well. This product is diluted with at least nine parts of water before it’s added to the pool, and each 4-ounce application of this product can treat 10,000 gallons of pool water. This product effectively deals a death blow to current algae blooms in the pool and can be used for pool maintenance as well.

5Sea Klear 90-Day Algae Remover & Prevention


Although pool owners have to be extra conscientious when they’re using this product and ensure that their pool is properly balanced in every respect, if that’s done, then this product can be used to prevent algae growth for up to 3-months at a time. It’s a reliable formula that destroys a variety of algae types include black, green, blue-green and yellow algae. It’s a non-foaming product that won’t stain pools. It contains 11.8% copper sulfate pentahydrate and can be used in a variety of different pools. It’s especially effective when used with a high-quality pool shock and an adequate pool filter.

4Clorox Pool & Spa Algae Eliminator


When most people think of Clorox, they think of laundry bleach, but this company also makes a pretty good line of pool algaecide as well. This product is called Pool & Spa Algae Eliminator, and as the name states, it’s capable of destroying algae in both pools and spas. Only 1.5 fluid ounces of this formulation needs to be added for every 10,000 gallons of water to keep all different types of algae at bay. It’s added while the filter and pump are in full operation and is meant to be reapplied whenever the system is refilled, drained, back-washed or after heavy rains.

3Bio-Dex Fast Acting Skill-It


If there’s a type of algae that can’t be killed by this product, we haven’t seen it. This high-quality formulation is made without the use of metals, so it won’t cause hair discoloration and also won’t stain swimming pools. It’s very easy to use by just about anyone, and it is designed to handle algae blooms for long periods of time. It can be added directly to the pool’s water, or it can be added to the pool’s water circulation equipment. Only 5.6-ounces of this product needs to be added to every 10,000 gallons of water a week for best results.

2Pool Mate Algaecide 50


This product is designed to effectively suppress algae growth in freshwater pools very efficiently. It can prevent that green, blue, or slimy yellow coating that can develop in swimming pools when algae begin to take over. This product is a quaternary algaecide that destroys all different types of algae, including mustard, yellow, black, green, and even pink algae. Only two to three ounces is needed a week to maintain a pool up to 10,000 gallons in size. Once applied to the pool’s water, the water is safe to be entered in 15-minutes, unlike other formulations that require the pool to not be used for hours at a time.

1McGrayel Algatec Concentrated Easy Care


This concentrated algaecide is designed to be easy to use and to quickly deal with all different types of algae. Once introduced according to its directions, this product is able to kill most forms of algae in anywhere from 8 to 24-hours, and can deal with black algae in approximately 10-days. This product is safe to use in all saltwater pools and has a formulation that doesn’t contain any bromides or heavy metals. It’s designed to work in coordination with your pool’s chlorine additives, instead of working against it like some formulations tend to do. This enables it to quickly eliminate yellow, green and black algae quickly.

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A Guide To Buying & Using Algaecides

As most pool owners already know, algae are something that can grow quickly and can take over a pool in no time flat. It’s also something that can be hard to kill. While chlorine does a great job of taking care of the things that we can’t see—namely bacteria and viruses—and does inhibit algae growth to a point, it can’t do everything. That’s why it’s important to purchase and use the best pool algaecides for your pool that are available.

In an attempt to help our readers more easily find the products they need to keep their pool looking and functioning well, we reviewed some of the best algaecide products above, and we think any of those products would do a great job for our readers. To help our readers narrow down their choices even further, we’ve decided to write this guide on the subject. This guide is designed to help our readers find an algaecide that will help them keep their pool clean, and also help them use these products effectively.

How To Choose A Great Algaecide

Anyone browsing our top ten list of the best algaecides, it’s easy to see that there are a wide variety of these products available. And that can make it difficult for people to choose which one might be right for them. Fortunately, most of the products on our list will do the job of killing algae and do it well. However, if you’re sourcing these products from someplace else, or simply want to look for some on your own, then be sure to look for products that contain the following ingredients:  copper sulfate pentahydrate, polyquaternium WSCP, ethylene dichloride, poly dimethylamino, or sodium bromide. All of those chemicals do a good job of destroying mustard algae, green algae, black algae, and pink algae, and blue-green algae.

How To Use Algaecide In Your Swimming Pool

Okay, once you’ve decided on an algaecide that you think will work well for your pool, it’s time to use that product to take care of any algae problems that might already exist and/or keep the pool algae-free going forward. Let’s take a look at some of the steps that the pool owner is going to want to follow to bring their pool’s chemistry back under control and keep it under control.

Items Needed:

Before you treat your pool for algaecide, you’re going to need a few pieces of equipment, and of course, the algaecide that’s going to be used. For this guide, the following tools are going to be needed to treat the pool for algae.

  • Test Strips
  • Pool Brush
  • Pool Vacuum
  • Chlorine Shock
  • Algaecide
  • pH Up or pH Down

Step One: Examine Pool Chemistry First

The absolute first step the pool owner should do is to make sure they do a test of their pool’s chemistry. There may be several reasons why algae have begun growing in your pool and those reasons can be an incorrect pH balance or a chlorine level that’s too low. If those problems aren’t corrected, then it will be harder for algaecide to get the job done. Therefore, it’s important to fix pool chemistry before starting the algae treatment.

Step Two: Superchlorinate Your Swimming Pool First

The next step is to make sure to super chlorinate your swimming pool. Superchlorination is also known as “pool shocking.” Shocking the pool raises the chlorine level several times higher than normal chlorine levels to ensure that the chlorine destroys resistant oils, compounds, and chemicals. Use a pool brush to clean the walls and floors of the pool thoroughly to remove any stuck on algae.

After shocking the pool, the pool owner should let the pool sit for approximately 24 to 48-hours to allow chlorine levels to return to normal. The chlorine levels must be in the proper range before using the algaecide to ensure that it works well.

Step Three: Apply The Product According To Directions

In this step, it’s important for the consumer to thoroughly read and understand their algaecide’s instructions. Once the directions have been thoroughly read, it’s important for the pool owner to add it precisely to their pool as detailed on the label.

Step Four: Allow The Algaecide To Sit 

After applying the algaecide, it’s time to let the pool sit according to the package’s directions. Most algaecides usually require the pool to sit overnight before the pool owner can move on to the next step.

Step Five: Vacuum The Pool

Using your favorite pool vacuum, make sure to thoroughly vacuum any and all dead algae that might be in the pool. If you previously missed any algae clinging to the stairs, walls, or floor of the pool, now’s the time to brush it off.

Step Six: Test And Adjust Pool Chemistry

Now that the pool is clean, it’s time to test the water so that it can be brought back into proper levels. Pay particular attention to pH and chlorine levels during this step, and adjust them as necessary.

Step Seven: Add Algae After Products To The Pool

Once pool chemistry levels are back in order, the pool owner might want to add a Polyquat algae concentration to their pool to keep it in good condition.

In Conclusion

As you probably noticed, treating your pool for algae isn’t as technical or as difficult of a process as some people think it is. All it takes is a willingness to pay attention to the pool’s chemistry, the best algaecide, the right tools, and a little bit of elbow grease. Algae can be a big pain, but if the pool owner stays on top of things it can easily be taken care of when it does rear its ugly head. Now all that’s left for our readers to do is to go out there, find a good algaecide and spend some time showing their pool a little bit of TLC. Anyone who does that doesn’t have to fear the yellow, black, blue-green, or green algae that might crop up.