Cloudy or milky swimming pool water is caused by seven main issues: improper levels of chlorine, imbalanced pH and alkalinity, very high calcium hardness (CH) levels, faulty or clogged filter, early stages of algae, ammonia, and debris.
How long does it take for a cloudy pool to clear? Depending on how cloudy your water is, it may take 2-3 days for your water to clear. If you're using a clarifier, you'll need to run your filter 24/7, keep your water chemistry balanced, and add the proper amount of water clarifier every other day until it's clear.
Very often, the reason that your pool is cloudy is simply because it is receiving insufficient filtration. Insufficient Filtration Time. Pools need 8 hours of filtration a day, and if you're pump isn't running long enough it's not going to be able to filter the water properly. Inadequate Filtration Equipment.
Excessive levels of pool chemicals can cause your water to become cloudy. High pH, high alkalinity, high chlorine or other sanitisers, and high calcium hardness are all common culprits.
Not to worry, this is normal and should resolve itself in a day or so as the chlorine level drops. Just keep your filter running in the meantime. If it doesn't clear up, either your filter-system is compromised, the rest of your water chemistry is out of whack, or you're using some cheap-ass, low-grade shock.
For the most part, yes. It can be unattractive and it should be addressed, but it is mostly safe to swim in cloudy water. The only exception would be if the pool is cloudy because there are too many chemicals in it. This pool water would be unsafe to swim in and should be avoided.
In theory, if you have a cloudy swimming pool, you can add chlorine to “shock it” and clear things up. Chlorine will get the job done. But, the amounts may vary and you may have to really pound the pool with chlorine to get the water totally clear.
Baking Soda
Most remedies call for adding additional chlorine into the water. If your water's pH balance is between 7.2 and 7.5, however, you can add baking soda to the water to help clear it up. This serves as a replacement for chlorine because baking soda is a natural cleaning agent.
The simple answer is No. Baking soda cannot be used to clear up a cloudy pool because it is a base. Bases raise PH levels, which causes the water to turn cloudy. Some people suggest using baking soda as a quick fix to high alkalinity levels, but it's not reliable as a pool chemical.
If the chlorine smell is very strong, however, you may soon spot “red-eyed” swimmers emerging from the pool. That's when the pool water is assumed to have “too much chlorine” in it. Ironically, a strong chemical smell around the pool and “swimmer red eye” may be signs that there is not enough chlorine in the water.
With a rain storm, any number of contaminants can be washing into your pool – acid rain, pollen, insects, tree droppings, dust, sand and even phosphates. Any one or combination of these things in rain can make your pool cloudy.
The water's pH may be too low or too high.
Lower than 7 indicates an acidic pool, but higher than 7.8 is too alkaline. A pool measuring at either extreme will likely be cloudy. High pH often indicates excess calcium deposits, and low pH often indicates more chloramine and less free chlorine.
Skim the top of the pool for debris that may have settled on the pool surface. Add one pound of diluted granular shock to the water for every 7,000 gallons of pool water. Run the filter for 24 hours and retest the water. The slimy looking film can be an early onset of algae.
Rapid pH Change
It drastically raises the pH in the water around it, which leads to clouding. This explains why the cloudiness does not happen all at once, rather the process creates a cloudy plume that slowly expands across the pool. This cloudiness is just calcium carbonate precipitating out of solution.
Here is why: Sunlight is white, which is made up of all the colours of the spectrum. The molecules in pool water absorb light from the red end of the spectrum when sunlight falls on the water. By removing the red, the light which ends up being reflected has a slightly blue hue which can vary in richness by water depth.
Algae is the primary reason for green water in your pool. Algae are normally kept in balance by water circulation, natural die-off in cool weather, and appropriate chemical balance. If the water circulation or chemicals are off, algae can bloom and cause a pool to be cloudy and green.
Having too much chlorine in your pool water can be dangerous. Exposure to high levels of chlorine can cause lung irritation, skin and eye damage, and provoke asthma. Not only is it bad for your health, but it can be bad for your pool due to the increase in chlorine.
It will take a while for the cloudiness to go away. For a sand filter, it will take a week or more. Cartridge filters will need to be cleaned more often than other filters during this process: twice a day for at least two days, or until the pool is clear.
Once the clarifier has been added to your pool, turn on the pool filter and run it 24/7 until the cloudiness is gone. This can take two to three days, but swimming in the pool at this time is safe after about 20 minutes.