Why Algae In Pool?

I often get asked this question. And my answer is,"Why not?"

Instead of looking at algae as the main problem, look at it as an indicator of underlying problems that your pool is currently facing. It's kind of like a headache. Either you can look at it as the main problem itself, and pop a pill or you could think of it as an indicator of something more serious and make a better decision based on that. You get the point?

So What Does Algae Indicate In The Pool?

Growth of algae indicates that the pool is:

  • high in nutrients (phosphates & nitrates)
  • has poor water circulation
  • has poor filtration
  • has low disinfection power (lacking chlorine)
  • has abnormal pH level (usually high pH)

Now for a minute, imagine algae never existed. Pool is crystal clear, but it still has all the above mentioned problems. And since there is no algae to indicate, you don't know that these problems even exist. How would they affect you? Here are some complications you'd face:

1. High Nutrients

People unintentionally drink water while swimming all the times. Drinking water with high levels of phosphates and nitrates is not good. High nitrates is fatal for babies under the age of 2 years. Also, wherever there are high nutrients, expect high levels of bacteria too. This makes water nasty to swim in.

2. Poor Water Circulation

Have you ever seen a stagnant pond? It's green in color, is full of bacteria, and parasites, mosquitoes, and it attracts all sorts of amphibians like frogs. If the pool was clear, you'd never even see most of the smaller parasites. 

3. Poor Filtration

Poor mechanical filtration can be extremely dangerous. There are hard-shelled parasites that are invisible to the naked eye. The shell keeps them safe from chlorination. These kind of parasites are feared in the water treatment industry, and rightfully so, because they cause stomach pain and all sorts of infections. They need to be properly filtered. 

4. Poor Disinfection

Poorly disinfected pool can be fatal for human beings. Disinfection is important to avoid infections, and other complications. Even a crystal clear pool can be unsafe for swimming. Algae simply indicates that the pool has no disinfection.

5. High pH

Strains of bacteria and algae grow in every range of pH. But at high pH, the chlorine becomes ineffective. Low chlorine efficiency results in low disinfection, which again leads to infections.


Thank your lucky stars that by simply having algae in your pool, you're able to catch all these problems before they can harm you. Think of algae as an alarm for your pool. By fixing the underlying problems, you co-solve the algae growth as well. Read this blog to truly fix all the algae issues in your pool.

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