Algae is a common problem in inground pools. The good news is that algae is something that you can treat on your own. Prevention is always key, but if algae finds its way into your pool, read on for solutions. There are even different types of algae, including green algae, yellow or mustard algae, and black algae. Treatments for each kind are similar but have some differences. Let’s look at why your pool might be green and how to get rid of the problem!
Pool Water Test Levels
Chemical levels are key to maintaining healthy pool water hygiene. For any of the treatments below, be sure that your chemical levels come back to the following ideal ranges:
- Free chlorine (1 – 4 ppm)
- pH (7.2 – 7.6)
- Alkalinity (80 – 150)
- Calcium hardness (200 – 275)
Green algae look like clouds and leave a murky, greenish tint. It is the easiest to prevent and treat.
Yellow or Mustard Algae
These algae are more yellow or mustard colored. It is more difficult to treat because it can attach to anything that enters the pool, including bathing suits, toys and floats. Be sure that all items have been thoroughly cleaned before reentering the pool.
Black Algae in Pool
These are most difficult to remove because of roots that attach to surfaces where it grows. Lots of scrubbing and more aggressive treatment are required if you find this type of algae. In a plaster pool, scrub with either a wire brush or a pumice stone after adding shock.
- Brush to thoroughly scrub floors, steps, walls and surfaces.
- Vacuum manually
- Test pool water levels.
- Add pool shock according to instructions and according to pool size. Remember that shock is most effective once the sun has set.
Green Algae: double dose of shock (x2)
Yellow or Mustard Algae: triple dose of shock (x3)
Black Algae: quadruple dose of shock (x4)
- Filter and circulate water for 24 hours.
- Test water again.
- Clean pool filter. Be sure to vacuum and/ or backwash pool to remove dead algae.
- Circulate water for 24 hours.
- Vacuum and/ or backwash the pool again to remove dead algae.
- If algae persist after 2-4 days, brush vigorously again and reapply shock.
Prevention is Key
To prevent algae from growing, make sure to:
- test and balance pool water weekly and keep levels within ideal ranges
- check filtration systems weekly
- brush and vacuum pool every 1-2 days
- shock weekly
- Clean toys and swimwear
There are also algaecides that may be added to your pool water in order to promote inhabitable conditions for algae to grow.
If you need help from experts, contact Millennium Pools and Spas! With 30 years of experience, we serve both residential and commercial customers in Virginia, Washington, D.C., and Maryland. We are 100% committed to helping our customers meet their needs. Contact us for more information.