How To Fix A Cloudy Or Green Pool After The Rain


A swimming pool with clear water just entices you to jump in. Combine this with hot summer days and it makes for a perfect recipe for relaxation and fun.

The same however cannot be said when it rains and the pool takes on a cloudy or green color. If you just installed your first swimming pool, you may wonder what to do after the rains and the option of emptying the pool and refilling it with clean water seems viable.

A few swimming pool tips could come in handy.

However, you do not have to do that. With a few tips, you can prevent the water from turning green in the first place, and in case it does, turn the water in your pool clear and inviting again.

But first…

Why swimming pool water turns green or cloudy after the trains

Rainwater is normally clean and there is nothing wrong with it getting into your pool. However, it does alter the chemistry causing the chlorine and other chemicals to dilute. This, in turn, creates a perfect habitat for green algae spores to grow and multiply making the pool cloudy after rain.

It is just a non-pleasant look.

Algae can cause a myriad of health problems such as eye and ear irritation, as well as gastrointestinal problems to both humans and pets. It’s important to observe the pet swimming pool safety guide.

What’s more, runoffs from other locations that may include harmful chemicals may find their way into the pool which further puts you at risk.

This is why it’s important to have a solution right before or after the rains.

How to prevent dilution

The first step in preventing algae formation after the rains are to keep the rainwater out of the pool in the first place. Start by cleaning and clearing all the debris surrounding the pool.

Next, get a pool cover and fix it over your pool. Ensure that your pool cover is made from high quality and durable materials as low-quality pool covers can tear and allow the rainwater to get inside the pool.

There are plenty of reasons why you should cover your swimming pool.

Once infiltrated, the chemicals in the pool will dilute making the pool green after rain. Another excellent way of preventing algae growth is by using an algaecide. It should kill off any algae spores that find their way into the swimming pool.

This makes it safe for everyone. If you have kids then it’s also great to follow the kids swimming pool safety guide.

Cleaning the debris

Sometimes you may have not gotten yourself a good pool cover in time and the rains found your swimming pool open and exposed. The algae grew and now your water is all green.

Do not despair as all is not lost. Start by removing any debris that found its way into the pool. Also, clean and vacuum any debris and dirt around the pool. You can do this with a pressure pool cleaner.

Check the filters and pipes and ensure that debris is not logged here as well. Check the steps and the ladder and make sure that there are no items or objects here as well.

There may be a lot of debris and dirt to deal with some of it is blown by the winds while others come with the runoff.

Maintaining the correct water level

Even with the pool green after rains, before you can rebalance the chemistry of your swimming pool, you will need to first bring back the water to the right levels. Most pools are designed to drain excess water on their own.

However, if yours doesn’t have such a feature, open the drain or the sand filter and let the water flow out to its optimum level. This is often near the middle of the skimmer float. A good skimmer basket will sieve out all the debris that has found its way into the water so make sure yours is in good condition.

Performing the test

After getting the water back to its right levels, it’s now time to perform tests to find out the alkalinity, ph. as well as the calcium hardness of the water. This will tell you whether or not the swimming pool is swimmable.

With the pool cloudy after rain, it is quite obvious that it is not fit for swimming. It would help to learn a few facts about pools, spas, swimming, and safety.

The rain may not be toxic or carry any harmful chemicals but it can have particulate matter. These could raise or lower the ph. of the swimming pool. Also, it’s always a good idea to add more chlorine especially if there were debris and plant matter that found its way into the water to help decontaminate from any germs.

The total ph. of your pool should be between 7.2 and 7.6 while the total alkalinity should be between 100 to 150 parts per million.

The calcium hardness, on the other hand, should be between 180 and 220 parts per million.  This is neutral and will help ensure that the concrete, as well as the walls of the swimming pool, don’t lose condition.

You can find out the condition of the water with the help of a pool test strip.

Running the pump


Check the entire filtration system from the pump to the pipes to the filter. Ensure they are in good working condition and that they are not clogged by any dirt or debris. Use a pool pole to get any debris out of the water.

Once satisfied, turn on the pump and allow it to run for at least 8 hours. It should take a lesser amount of time to filter the water especially if you are using diatomaceous earth.

If you are using a sand filter, then it could take a couple of days to filter the water.

To ensure that the filter is working at its optimum, it’s a good idea to perform regular checks and maintenance. You can wash the filter with a hose or you may find the need to change it regularly.

Shock the pool

After observing the steps to open a swimming pool, if you noticed that the pool was excessively pooled cloudy after rain, you might need to shock the pool. The first thing you will need to do is ensure that the filtration system is working well. Also, check the chemical balance in the pool.

Now, take your chlorine shock and mix it up well. You can do this by taking a pound of the shock treatment and mixing it with 5 gallons of water. Never add the shock treatment onto the skimmer directly without first diluting it.  This is because it could damage the pool heater, pool pump, or pool filters.

High shock levels will help kill all the algae. This may require you to make multiple treatments and may take several days. Make sure to brush the pool and clean it every day very thoroughly to take out the dead algae. You should also be conversant with how to clean the tile at the swimming pool waterline.

Other useful tips for cleaning your pool

When it comes to the chlorine that you use on your pool, you should know that it is available in two main forms—stabilized and unstabilized. The stabilized type features a cyanuric acid coating. This stops it from evaporating when added to the pool during the day.

The unstabilized chlorine doesn’t come treated with cyanuric acid.

The other name for unstabilized chlorine or sodium hypochlorite is pool bleach. It comes as a liquid that is more iconic than household bleach. On the other hand, calcium hypochlorite is also used to shock the swimming pool and comes as granular particles and is also highly effective at shocking the pool green after rain.

Calcium hypochlorite, however, will react quickly but takes more time to dissolve completely. It is always a good idea to shock your pool at night so the chemical doesn’t evaporate fast in the sun. You will have to wait at least 8 hours for you to get into the pool.

Always check the instructions that come with your pool shock to make sure you add the right quantity in the right way. If you are in doubt as to how to add the chemicals, don’t hesitate to seek the services of a professional. You will get better results.

When everything else is in order, you can take advantage of the warm sun to repaint the deck of your swimming pool using the best pool deck paint you can find.

Preparing the pool for the oncoming rains

We already saw how important it is to clean the pool and the area around it and to cover it with a high-quality pool cover. A good pool brush should get the job done.

To add on that if there is any furniture or objects that are not tied to the floor, these need to be removed from the poolside and stored somewhere inside the house. These could include, grills and smokers, patio furniture, lounge chairs, pool toys, and floats as well as any other decorative units such as potted plants.

Second, ensure that all electrical systems connecting to the pool are turned off. This means the pool pump and the pool heater. If you are using an automatic pool pump switch, ensure that it doesn’t turn on at the preset time during the storm.

Also, check that the gas line is turned off as well. This will lower the chance of the gas leaking. Now that everything is back in check remember to observe 10 swimming pool etiquette tips while swimming.

Globo Surf Overview

After the pool turns cloudy or green after the rains, it looks so different that it’s hard to imagine that just a short season ago the water was crystal clear. It looks unpleasant and only a mad man would enjoy getting into that awful looking water.

However, you don’t have to empty the water and refill it with clean water. All you need to do is to observe the tips above and within a few days, the pool water should be sparkling clean.

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My name is David Hamburg. I am an avid water sports fan who enjoys paddle boarding, surfing, scuba diving, and kite surfing. Anything with a board or chance I can get in the water I love! I am such a big fan I decided to start this website to review all my favorite products and some others. Hope you enjoy!