Should I Shock My Pool? 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.
Shock & Filter the Water
Shocking helps sanitize any contaminants or materials that were introduced to the water during the storm. Run your system for at least 12 hours to ensure proper filtration and circulation. This removes dirt and debris, and also assists with circulating the chlorine throughout your pool.
A big rainstorm is going to add lots of contaminants to your pool, so it never hurts to shock your pool before an anticipated storm. However, there's no harm done if you aren't able to do so. After the storm passes, you can shock your pool and then bring us the water sample so you can rebalance it.
Again, you need to know about the weather ahead of time: as always, you should only add pool shock at dusk or night. I hate to have to tell you this, but rain can also introduce algae into the pool. This is because there are algae spores in the air, which can attach to rain drops.
But large quantities of precipitation combined with an overflowing pool and poor drainage can cause problems such as flooding, structural damage to the surrounding buildings as well as out of balance swimming pool water chemistry. No fun.
A small amount of rain will have little to no effect on your pool. However, when a storm dumps 1 to 3 inches of water in a short period, it could take a toll on your pool water.
If your pool is completely full after a storm or heavy rainfall, you don't need to take drastic steps such as emptying your pool. If you do, the hydrostatic pressure can cause your pool to come out of the ground.
At the first sign of an incoming storm, you should turn off and unplug your pump. If this is left running during a storm, the motor may suffer electrical damage and short out.
When preparing your pool for a storm, leave it uncovered. Installing any kind of cover across the pool will not do much to protect against dust and contaminants because storms often bring strong winds and heavy rain that can cause the cover to lift off your pool.
Shock the pool
It's not time to fix your pool chemistry just yet – that said, there's nothing wrong with giving your water a little boost. After heavy rainfall, your pool's chlorine levels will be much lower from fighting off contaminants. Shocking your pool replenishes the chlorine lost from the rain.
Heavy rains will dilute your pool alkalinity level, causing it to fall by 5-10 ppm a day. Low Alkalinity and low pH levels in pools can create a corrosive water environment. Corrosive pool water can result in the damage of underwater metal surfaces, such as pool lights, ladders and rails.
Answer: It should not matter much. It could help to filter debris and contaminants the rain washes into the pool. However, lightning can be a concern with the filter running.
If the pool overflows, now only will the pool chemicals be diluted, but they may contaminate the pool deck and surrounding landscape. Removing excess water quickly is important to prevent this.
"Heavy rain dilutes pool chemicals, especially salt and chlorine, which causes the pool to turn green. This means the water is not sanitised or healthy, so it's vital to address this.
Shock Your Pool with Chlorine to Kill Algae
This is the main event in clearing a green pool—killing the algae. Pool shock contains a high level of chlorine that will kill the algae and sanitize the pool. For the best results, use a shock that contains at least 70% available chlorine (calcium hypochlorite).
One fast way to turn your pool water green is by accidentally adding chlorine to a pool with bromine. You are suppose to shock bromine pools with chlorine, just make sure not to mix the two chemicals, and do not add to much chlorine. Usually the green will go away fast if you do not add to much chlorine.