High chlorine levels decrease the pH of your pool's water, making it more acidic. The more acidic the water, the higher the likelihood of corrosion. This corrosion can affect metal piping, equipment, and the surface of your pool (tiles, liners, concrete, etc.).
7. Using liquid chlorine raises the pH of the water. Liquid chlorine does not raise pH. When added to water, liquid chlorine (which has a pH of 13) makes HOCl (hypochlorous acid – the killing form of chlorine) and NaOH (sodium hydroxide), which raises pH.
Two reasons. First, the germ-killing power of chlorine varies with pH level. As pH goes up, the ability of chlorine to kill germs goes down. Second, a swimmer's body has a pH between 7.2 and 7.8, so if the pool water isn't kept in this range then swimmers will start to feel irritation of their eyes and skin.
Here are common causes of an alkaline pool: Algae can raise the pH. Adding strong liquid chlorine, calcium or lithium hypochlorite chlorine may raise it.
Most people know that chlorine is an important chemical in keeping pool water safe for swimming. But adding too much chlorine can lower your pool's pH as well as its total alkalinity. When alkalinity falls, it is more difficult to maintain a stable pH.
The PH rise is temporary, and as the chlorine is used up the ph will drop back to normal. Disregard high PH readings. We recommend shocking with liquid chlorine - granular products add additional things that you may not want in your pool. Non-chlorine shock is really meant for use in spas, or indoor pools.
Test the pH level
The most optimal and effective pH level to shock a pool is anywhere between 7.2 and 7.4. If the pool water is anywhere outside of this range, the water will not be suitable for the shock, making the treatment significantly less effective.
Proper pool pH is right in the middle — pool pros recommend that pH be between 7.3 and 7.6 for optimum performance and cleanest water. If the pH gets higher than 7.8, the water is becoming too alkaline.
Non-stabilized chlorines like calcium hypochlorite (cal hypo), sodium hypochlorite (liquid chlorine), and salt chlorine generators all tend to raise the pH of the pool. One common habit in the pool business is to add some acid to "offset" the pH rise that liquid chlorine causes.
You can lower the pH in your pool naturally by directing the downspouts from your house into the pool. If a pool becomes too full due to backwash it dumps water. Since rain is about 5.6 pH it is going to bring down the pH of the water naturally. The problem that you will have with rainwater is its low alkalinity.
High chlorine levels decrease the pH of your pool's water, making it more acidic. The more acidic the water, the higher the likelihood of corrosion. This corrosion can affect metal piping, equipment, and the surface of your pool (tiles, liners, concrete, etc.).
To raise your pool pH levels, try adding in sodium carbonate (AKA soda ash). Make sure that you don't add any more than two pounds of soda ash per 10,000 gallons of water per treatment. When adding in the soda ash, start adding from the deep end of your pool and work your way up to the shallow end.
Add soda ash if your pool's pH level is below 7.2. Add Muriatic Acid or Sodium Bisulfate if it's above 7.8. Continue to add appropriate product until your water has a pH level of 7.2-7.8 (ideally 7.4-7.6).
We recommend adding Acid weekly! Adding a little and often is better for your water and can actually save you money overtime. Large doses over longer periods of time take a larger portion of your 'Total alkalinity' away.
Use a pool test kit to check the pH, acid demand, and total alkalinity. Once you've determined that the pH level is too high, you should now work to restore the balance. There are two main products for lowering the pH. These are sodium bisulfate (also known as dry acid) and muriatic acid.
In most cases, low pH levels are caused by natural factors like a heavy rainstorm, overuse, and improper use of chemicals. Natural rainwater has a pH of 5 – 5.5, so it is naturally acidic. A substantial amount of rainfall can alter the pH of pool water to become more acidic.
Low pH water will cause etching and deterioration of plaster, grout, stone, concrete and tiling. Any vinyl surfaces will also become brittle, which increases risk of cracks and tears. All of these dissolved minerals will hold in the solution of your pool water; which can result in staining and cloudy pool water.
Rainfall dilutes pool chemistry levels and lowers the readings for pH, alkalinity, hardness, stabilizer, and chlorine. Rainfall does not contain chlorine.
If the pool is still very cloudy or green, you may need to shock it to make it safe to swim in again. First, make sure that the filter system is working properly and the chemicals are still at the proper levels. Next, mix up your chlorine shock (hyperchlorinate) treatment.
Remember, rain is acidic. Hence, pool overflowing from rain causes the Alkalinity and pH levels to lower. Very low pH causes pool water to turn very clear and acidic, which destroys your pool surface and equipment.
If your pool pump manufacturer has declared your pump is rain safe, you can leave it on in rainfall. Nevertheless, during a thunderstorm, it is highly recommended that you switch off and unplug your pool pump to prevent any costly and irreversible damages to your pool equipment.
Remember that a Low pH level is crucial to successfully shocking a pool. At a pH level of 8.0, over half of your shock is ineffective and wasted. At a pH level of 7.2 however, over 90% of your shock will become active algae and bacteria killers.