"Heavy rain dilutes pool chemicals, especially salt and chlorine, which causes the pool to turn green.
It is a fact that rain will decrease your Total Alkalinity level in the pool over time, requiring a pool owner to raise the alkalinity. Rainwater has a Total Alkalinity near zero. Heavy rains will dilute your pool alkalinity level, causing it to fall by 5-10 ppm a day.
Shocking your pool isn't necessary, although, it's not a bad idea either. If you get an extremely heavy rain fall, you could shock your pool for good measure. This will help fight off any contaminants that the rain may have brought to your pool.
Effect on Pool Water pH
Since rain is diluting your pool, you may expect that it will reduce the acidity of your pool water. However, all rain in the US is acidic due to pollution, so rain actually decreases your pool's pH – in other words, the pool water becomes more acidic.
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.
The most common reason pool water turns green is due to algae growing in the water. Algae can grow rapidly, particularly in hot weather, which is why it can surprise you overnight during the warmer months. This generally comes down to an imbalance or lack of chlorine in the water.
The free chlorine levels might be low.
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.
What's important for you to know: You shouldn't swim in a pool that's green until you test the chemical levels, like the officials in Rio did before the diving event began. It's the balance of things like chlorine, pH, and alkalinity in a pool that keeps it sterilized.
Baking Soda and Green, Blue, or Yellow Algae
You'll need to use an algaecide to kill the algae and superchlorinate your pool to clear the water. After this treatment, test your pH and alkalinity and add baking soda to raise alkalinity to at least 100 ppm and pH to between 7.2 and 7.8.
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.
The solution to maintaining a clear pool is to use readily available liquid bleach as your chlorine source. Chlorine bleach, as discussed above, is not bound to a stabilizer, so when you add chlorine bleach to the pool, it will go right to work killing microbes and sanitizing.
It is important to know what exactly bleach is before you put it in your pool. Household bleach, Clorox and liquid chlorine can all be used to sanitize a pool. They are all types of chlorine. Household bleaches such as Clorox usually contain about 5-6% available chlorine, about half that of pool liquid chlorine.
Just like you run vinegar through your coffee pot to get rid of calcium buildup, white vinegar can wipe away this eyesore in your pool. Mix a 50/50 solution of vinegar and water, dip a sponge or soft cloth into it, and scrub that residue away.
Natural Cleaning Agents for Pools
Baking soda: This is a great cleaning agent in general that also works well in swimming pools. The active ingredient in baking soda is sodium bicarbonate, which breaks up algae and allows you to scrub it and clean it from your pool.
Baking soda does not directly reduce the chlorine. Adding too much chlorine or too much acid can lower ph and, with it, total alkalinity — which is a measure. Of baking soda per 10,000 gallons of water will raise alkalinity by about 10 ppm.
Answer: It is true that pool chlorine is stronger than bleach. For bleach and water to be the same strength as pool chlorine and water, you would have to adjust the ratio, increasing the bleach and reducing the water. But no matter which chlorine you use, make sure to test a small area before doing the job.
Chlorine is a sanitizer, and (unless you use Baquacil products) is necessary for maintaining a clear and healthy pool. Shock is chlorine, in a high dose, meant to shock your pool and raise the chlorine level quickly.
There are alternatives to chlorine including bromine, ionizers, and ozonators, though with each you'll still need to use some chlorine. A fourth alternative is PHMB, which doesn't require the use of any chlorine. All four have drawbacks, including cost.