Mustard Algae | What Is It? How Can I Fix It?

Top 5 Products To Eliminate Mustard Algae In Swimming Pools

Mustard algae is a difficult and frustrating problem for swimming pool owners everywhere. Also called yellow algae, this form of algae ranges in color from bright yellow to greenish yellow, and tends to grow on pool walls, as well as other surfaces, including all pool equipment, lights, floats, toys, and swimming suits. Mustard algae treatment can be a tedious process due to the persistent nature of the algae. While chlorine alone is sufficient to treat other types of algae, yellow algae requires an additional chemical to be fully eliminated. Luckily, there are multiple high-quality, dependable products currently on the market to counteract this pesky swimming pool issue. With the right product and a strong treatment plan, you will be back swimming in a clean, clear pool in no time.



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Kem-Tek KTK-50-0006 Pool and Spa 60-Percent Concentrated Algaecide, 1 Quart

Kem-Tek KTK-50-0006 Pool and Spa

1 Quart


GLB Pool & Spa Products 71114 1-Quart Strike Out Algaecide

GLB Pool & Spa Products 71114

1 Quart

treated water can
be swam in immediately

United Chemicals Yellow Treat® 2 pound container

United Chemicals Yellow Treat



Applied Biochemists Yellow Trine Yellow Mustard 408622

Applied Biochemists 408622



Jack's Magic JMYELLOW2 The Yellow Stuff Pool Algaecide, 2-Pound

Jack's Magic JMYELLOW2


99% sodium

Top Product List

Kem-Tek Pool And Spa 60% Concentrated Algaecide

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As the #1 Best Seller in the “Swimming Pool Algaecides” category on Amazon, this product from Kem-Tek is one of the most popular algae treatments available. And, with an average rating of 4.3 out of 5 stars across 442 customer reviews, this product is known to have worked for countless pool owners. The concentrated, non-foaming formula cleans and purifies water to clear up even the most stubborn mustard algae in a pool. Not only does Kem-Tek’s algaecide tackle any existing algae, but it also helps to prevent future outbreaks. This product is compatible with all pool and filter varieties, including saltwater pools.

GLB Pool & Spa Products Strike Out Algaecide

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This algaecide from GLB is specifically designed to eliminate green and yellow algae in pools, with a long-lasting and concentrated formula comprised of 7.4% copper. The powerful formula is fast-acting, allowing you to get back in the pool immediately after treatment. GLB’s Strike Out Algaecide is also effective and safe for use in saltwater pools, as well as with chlorine, ozone, and bromine sanitizers. Be sure to dilute this product before use, referring to the dilution chart provided on the bottle. With an average customer rating of 4.4 stars out of 5, this algaecide from GLB is one of the best options available to remove mustard algae in a pool.

United Chemicals Yellow Treat

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Yellow Treat from United Chemicals is one of the longest standing mustard algae treatments available, earning 4.2 out of 5 stars on Amazon. Specially tailored to the unique characteristics of yellow algae, this product uses a sodium bromide-based formula to quickly eliminate the algae. In addition, Yellow Treat will add a polished shine to your pool surfaces for added cleaning power. This algaecide comes in powder form, making it easier to apply and safer for use around families and pets. A 2-pound container of Yellow Treat sells for just $19.82-- a fantastic price for this reliable, effective pool care product.

Applied Biochemists Yellow Trine Yellow Mustard

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With an average rating of 4.8 out of 5 stars on Amazon, the Yellow Trine algaecide from Applied Biochemists is trusted by many to produce excellent results. The fast-dissolving granular formula works to remove tough yellow algae in a pool without leaving behind any residue. Yellow Trine also helps to hinder future yellow algae outbreaks, decreasing the need for future mustard algae treatment. This pool care product is safe for use in all types of pools, so you do not have to worry about chemical incompatibilities. One 3-pound bottle of Yellow This product is an affordable option for those desiring to purchase a larger amount of algaecide at once.

Jack’s Magic The Yellow Stuff Pool Algaecide

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Jack’s Magic is a worldwide leader in swimming pool stain removal treatments. This product, The Yellow Stuff, is specially designed to quickly clear up mustard algae, leaving your pool and pool surfaces clean and looking like new. It is safe to use with any type of pool finish, and won’t leave behind residue. The Yellow Stuff is also compatible with all of the main swimming pool sanitizers. Comprised of 99% sodium bromide, this algaecide dissolves quickly, allowing you to get back in the pool within just a couple of hours. The Yellow Stuff has earned a review of 4.8 stars on Amazon.


The appearance of mustard algae can be a major setback in the enjoyment of your swimming pool. Not only is this form of algae unsanitary, but it also tends to be difficult to remove. Fortunately, pool owners today have access to an array of effective, powerful products which will work to clear up yellow algae in pools. You do not have to spend large amounts of money to achieve clean, sparkling pool water; all of the fantastic mustard algae treatments listed above are on sale for under $25. No matter your pool sanitation type or variation of swimming pool surfaces, there is a pool care product available to fit your needs. Mustard algae may be a nuisance, but there are several great product options to clarify your pool water and get back swimming in no time.

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Kem-Tek KTK-50-0006 Pool and Spa 60-Percent Concentrated Algaecide, 1 Quart
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