Why is My Pool Green

If you’re a pool owner, you’ve probably encountered the dreaded sight of greenish cloudy pool water before- algae has contaminated your pool.

It can happen to the best of us- things get busy, life gets in the way, impurities can get introduced into the pool, and maintaining the right chemical balances in the pool gets forgotten. 

We’ve put together all the information you’ll need to know, from what it is, what causes it, to the most important thing to know- how to get rid of it and how to keep it from coming back.

What is Making it Green?

So, you’ve noticed your pool is turning green, and the first thing you’ll probably want to know is what it is.The unwanted guest in your pool is green algae! The technical name for this green algae is chlorophyta, which is a cyanobacteria, meaning it gets its color from chlorophyll. 

Algae is a microorganism that grows in any water unless there is a sanitizer continually being added faster than the algae can grow. 

In traditionally maintained pools, the algae occurs because the pool isn’t getting consistent sanitation, so there is not enough free chlorine (when the level is below 1 ppm), so the algae is at a prime stage to multiple and grow, meaning you’ll have a huge problem in a very short timeframe, with a lot of green algae to kill.

So with chlorine pools, in order to avoid getting algae in your pool, you constantly have to be making sure your sanitizer is at the right level and constantly keep adding sanitizer to make sure you don’t have algae problems, which is a huge hassle. 

When these conditions are left unattended, it can begin to harbor more dangerous bacteria, parasites, & pests; it could make pool accessories and floors slippery which means there’s a potential for injury; and can also clog your pool filters which can exacerbate the issue, so it’s best to take care of it as soon as you start seeing it appearing, even in the smallest of amounts.

What causes it?

There are many common causes for green algae, and they are all related to the environment in which the spores thrive. Conditions like water chemistry making your chlorine levels ineffective , warm temperatures, dirty swimsuits, organic waste, or even the rain, wind or sunlight can contribute to the growth of green algae and cause it to quickly multiply. 

To put it bluntly, the deck is stacked against you; the sanitation provided by the chlorine in your pool water is the only thing that keeps your pool from reverting into a pond. 

Because they contain chlorophyll, the algae spreads especially rapidly in warm, sunny environments because it uses photosynthesis to grow. The warmer the temperature, colonies of microorganisms can double in size in just a matter of hours. 

That’s why during the summer, when the pool is not only getting frequent use, but also when the temperatures are higher, it is so important to maintain regular pool maintenance and regular checks of the water’s chemistry are crucial to having a safe and clean pool.

Even though this is a treatable algae, it can cause a huge headache, especially when the algae comes back. Once spotted, it needs to be attended to immediately. If the water is left unattended, the algae will spread like wildfire and cause a multitude of problems within your pool and pool equipment, and become increasingly harder to fight off. 

Typically, pools that use traditional chlorination eventually fall into this vicious cycle: in order to prevent algae, chlorine pools require constant upkeep and when it's not done perfectly, algae gets a foothold and even more chemical maintenance is required to combat it. Once you’ve experienced this you realize that it is a tremendous hassle, and it also means a greater expense for you as well.

How do I prevent it?

Simply put, green algae, and all algae infestations, are a headache and a big expense to take care of. Algae is prevented by ensuring a free chlorine level of 1-3ppm in the pool, every day. However, your pool chlorine is always getting used up, so the trick is finding an easy way to maintain that level.

 If you’ve ever experienced an algae infestation first hand or you’re worried about it ever happening to you and are trying to prevent it, do yourself a huge favor and get a salt chlorinator. 

With salt pool systems, algae infestations don’t generally occur, because a salt chlorine generator system automatically provides consistent sanitation every day, unlike a traditional pool system. 

Otherwise, without a salt system, the way you prevent algae is through diligent manual effort: measuring, mixing, adding, and maintaining just the right chlorine levels every day using liquid, granular, or tablet chlorine.

In other words, algae problems can occur in any pool that isn’t maintained correctly. It’s good to generally try and stay up to date with your pool, keeping debris, leaves and dirt out of your pool. But the most important pool maintenance happens at the microscopic level. 

Keeping a clean pool and balanced water chemistry all revolves around ensuring that there is a constant “shield” of chlorine that is able to effectively sanitize and destroy the algae trying to grow in the water. 

With salt water pools, it's easy to consistently have enough free chlorine in your pool to avoid algae issues just by keeping your salt chlorinator for the right settings for your pool, so that you’ll always have a consistently beautiful and clean pool.