A pool turns green when there is algae in the water. There are several reasons why algae could grow, but it is most commonly caused by prolonged exposure to the sun, rain and temperature spikes. These factors affect the chemical balance of the pool and result in the pool turning cloudy and/or green.
Pool water turns green because of algae in the water. Algae can grow rapidly, particularly when it's warm like Summer, which is why it can surprise you overnight. This generally comes down to an imbalance or lack of chlorine in the water.
When the levels are properly balanced, chlorine will keep the algae at bay, but the water will slowly begin to turn green as the algae take over if there's not enough. But be careful—adding too much chlorine in pool water can cause those metals to oxidize and turn the pool a different shade of green.
The use of baking soda in pools can spot treat algae
No one ever wants to see algae build up in their swimming pool. It can turn any backyard pool murky green or cause unsightly black spots on the walls and floor of any swimming pool.
Pools can immediately turn green after shocking when they have metals like copper in the water. These metals oxidise when exposed to high levels of chlorine which makes the pool water turn green. Adding a metal control product such as Zodiac Metal Remover will help to restore the pool water.
Is it Safe to Swim in a Green Water Pool? Short answer – it depends. Lakes contain a full ecosystem, complete with aquatic life that feeds on bacteria and toxins. This makes swimming in green water in nature safe.
Light Green or Teal Pool Water:
This means there's a low amount of algae in your water and you won't have to use a hefty amount of chlorine shock. In this case, you should double shock your swimming pool water. To double shock, you will need to add 2 pounds for every 10,000 gallons of water.
1. Shock the pool with chlorine every day until all the green is gone (possibly 3 to 4 days). 2. Run the filter 24 hours a day and backwash every day until the green and then cloudiness is gone (usually up to 7 days, sometimes as long as 2 weeks depending on the filter).
Algaecide should be used after each shock treatment, so it has a better chance to support your chlorine as it works its magic. Be sure to shock your pool first, then when the chlorine levels of your pool return to normal, add the correct amount of algaecide to several places around your pool while your pump is running.
You can also simply add more chlorine, and pouring household bleach into the pool is one way to do this. Be sure the pH is in the proper range -- between 7.2 and 7.8 -- and add the bleach in the early evening to avoid having most of it degraded by sunlight.
ADD POOL CLARIFIER
The change in your pool water colour means that you have successfully eliminated the algae and can now clean it out of your pool. If your water is still green, wait another 24 hours and redo the steps from Days 1 and 2.
Clarifier does take some time to work, unlike flocculent. It usually takes 3-5 days. From the time you put the clarifier in the water, you'll need to filter your water for at least the first 24-48 hours, then as much as possible. Note that if you have algae, you should take care of that before using clarifier.
Baking soda, also known as sodium bicarbonate is naturally alkaline, with a pH of 8. When you add baking soda to your pool water, you will raise both the pH and the alkalinity, improving stability and clarity. Many commercial pool products for raising alkalinity utilize baking soda as their main active ingredient.
A pool filter should be run for a minimum of 6 hours after shocking a swimming pool. This is to allow the filter to clean the water and give the shock enough time to fully mix with the pool water. Running the filter after shocking for 24 hours to 7 days is necessary if the pool has a large amount of algae.
Pools can immediately turn green after shocking when they have metals like copper or iron in the water. These metals oxidize when exposed to high levels of chlorine which makes the pool water turn green. Metals in the water are caused by some algaecides and using well water.
Algae growing over larger sections of the pool, or suspended in the water will require a strong dose of chlorine pool shock, or granular chlorine, to kill the algae.
The presence of too much algaecide can lead to a foamy pool water. Small bubbles will begin to be produced as the water is pushed through the return jet and back into the pool. Do not confuse these bubbles and foam with another common problem, which is air in your pool lines.
Chlorine—yep, your typical sanitizer—is much more effective at killing algae than algaecide is. Even if your water gets cloudy and your walls get slimy, chlorine can still kill it. That's because chlorine oxidizes bacteria and single-celled algae, which means they trade electrons.
GETTING RID OF ALGAE
Liquid Algaecide is a strong algae depressant used for the prevention of algae growth and the maintenance of sparkling water in pools. Algae growth is the main cause of “off” colours in your swimming pool water.