Austin Algae: Pool Shock Fueling Scalp Yeast?

By Franklin Everett Shaw

March 24, 2026

Itchy scalp got you down after a dip in Barton Springs or Deep Eddy? That persistent flaking might be more than just dry skin. For many Austinites, the combination of hard water, pool chemicals, and even the algae itself can trigger a Malassezia yeast overgrowth, leading to seborrheic dermatitis or pityriasis versicolor on the scalp. Let’s dive into how to identify, treat, and prevent this common Austin ailment.

Malassezia is a type of yeast that naturally lives on everyone’s skin. It’s usually harmless. However, certain conditions can cause it to multiply excessively, leading to inflammation and those tell-tale flakes.

Austin’s unique environment creates the perfect storm. Think about it: we’re constantly exposed to chlorine and other pool shock chemicals during the summer months. These chemicals strip the scalp of its natural oils, disrupting the delicate balance of the scalp microbiome.

Then there’s the hard water. Austin’s water supply is notoriously high in minerals like calcium and magnesium. These minerals can further irritate the scalp and make it more susceptible to yeast overgrowth.

And let’s not forget about the algae blooms that sometimes plague our beloved swimming holes. While the direct link between algae and Malassezia is still being researched, some experts believe that exposure to certain types of algae can exacerbate skin conditions.

So, how do you know if you’re dealing with a Malassezia overgrowth? Common symptoms include:

• Itchy scalp, often intense.
• Flaking, which can range from fine and powdery to thick and greasy.
• Redness and inflammation.
• Dandruff that doesn’t respond to regular anti-dandruff shampoos.

If you’re experiencing these symptoms, it’s time to take action. The good news is that Malassezia overgrowth is usually treatable with over-the-counter or prescription medications.

First, let’s talk about preventative measures. The best defense is a good offense, right?

• Rinse your hair thoroughly after swimming. This will help remove chlorine and other pool chemicals. Use bottled water for a final rinse to combat hard water.
• Wear a swim cap. This will minimize exposure to pool chemicals and algae.
• Limit your time in the pool. The less exposure, the better.
• Use a clarifying shampoo regularly. This will help remove buildup and keep your scalp clean.

Now, let’s talk about clarifying shampoos. Many clarifying shampoos are too harsh for colored hair, stripping it of its vibrancy. But don’t worry, there are options!

Look for clarifying shampoos that are sulfate-free and specifically designed for colored hair. These shampoos will gently cleanse your scalp without damaging your color.

Here are a few recommendations you can find at Whole Foods Market or Central Market in Austin:

• Acure Buildup Balancing Hemp & ACV Shampoo: This shampoo is sulfate-free and contains apple cider vinegar, which helps to balance the pH of your scalp.
• Giovanni Tea Tree Triple Treat Invigorating Shampoo: This shampoo contains tea tree oil, which has antifungal properties.
• SheaMoisture African Black Soap Dandruff Control Shampoo: This shampoo contains African black soap, which is known for its cleansing and clarifying properties.

When using a clarifying shampoo, be sure to follow the instructions on the bottle. In general, you’ll want to use it once or twice a week, depending on the severity of your symptoms.

If over-the-counter treatments aren’t working, it’s time to see a dermatologist. A dermatologist can diagnose your condition and prescribe stronger medications, such as:

• Prescription-strength antifungal shampoos: These shampoos contain ingredients like ketoconazole or selenium sulfide, which are more effective at killing Malassezia yeast.
• Topical corticosteroids: These creams or lotions can help reduce inflammation and itching.
• Oral antifungal medications: In severe cases, your dermatologist may prescribe oral antifungal medications.

Here are a few dermatologists in the Austin area who specialize in treating scalp conditions:

• Dr. Adam Mamelak at Sanova Dermatology: Known for his expertise in medical dermatology.
• Dr. Ted Lain at Austin Institute for Clinical Dermatology: Offers a wide range of treatments for skin and scalp conditions.
• Dr. Miriam Hanson at Westlake Dermatology: Provides comprehensive dermatological care.

Don’t be afraid to ask your dermatologist about the potential role of hard water in your scalp condition. They may recommend using a shower filter to remove minerals from your water.

Another often overlooked factor is diet. Malassezia thrives on certain types of fats. Consider reducing your intake of processed foods, sugary drinks, and unhealthy fats.

Instead, focus on eating a healthy diet rich in fruits, vegetables, and lean protein. This will help support a healthy scalp microbiome.

One common mistake people make is over-washing their hair. Washing your hair too often can strip your scalp of its natural oils, making it more susceptible to Malassezia overgrowth.

Try to wash your hair only when it’s necessary, and use a gentle shampoo.

Another pitfall is using too many styling products. Hair sprays, gels, and mousses can create buildup on your scalp, which can feed Malassezia yeast.

Use styling products sparingly, and be sure to wash them out thoroughly at the end of the day.

Finally, remember that treating Malassezia overgrowth can take time and patience. Don’t get discouraged if you don’t see results immediately.

Stick with your treatment plan, and be sure to follow your dermatologist’s instructions. With the right approach, you can get your itchy, flaky scalp under control and enjoy all that Austin has to offer, from Zilker Park to the Greenbelt, without the constant discomfort.