Shocking Your Swimming Pool- What is it and What does it do?

Shocking Your Swimming Pool- What is it and What does it do?

Shocking your swimming pool is an essential maintenance step that involves adding a concentrated dose of chlorine to the water.

The purpose of shocking is to prevent or resolve specific issues such as bacteria growth, algae formation, and the presence of chloramines. Here's a breakdown of what shocking does and why it's necessary:

1. Algae Removal: Algae can quickly multiply and cause damage to your pool. Shocking with a combination of algaecide helps destroy algae by breaking through their protective shells and disrupting their cellular processes. The amount of shock needed depends on the severity of the algae infestation, ranging from 10 ppm for light green or isolated algae to 30 ppm for dark green or black algae. It's recommended to vacuum, brush, filter, and use a pool clarifier before and after shocking to effectively clear up the pool water.

2. Bacteria Sanitization: Pool water can harbor bacteria, viruses, and parasites, posing health risks. Routine sanitation measures and filtration help prevent and remove most bacteria. However, after heavy pool use or when the chlorine levels have been low for an extended period, shocking the pool is recommended. Testing for bacteria using a bacteria test kit will determine the extent of contamination. The amount of shock needed to kill bacteria varies based on the bacterial load, with 30 ppm often being the target. For example, E. coli requires 2-3 ppm of chlorine to be effectively eliminated.

3. Chloramine Reduction: If your pool water has a strong chlorine smell, it indicates high levels of chloramines, which are byproducts of chlorine combining with contaminants like sweat and urine. Despite the chlorine odor, the pool still needs to be shocked. Using a DPD test kit to measure Free Available Chlorine (FAC) and Total Available Chlorine (TAC), you can determine the appropriate shock level. Typically, you need to shock the pool to a level that is 100 times greater than the current chloramine level.

To determine how much shock is required, you need to reach the breakpoint chlorination level where molecular bonds break apart, removing bacteria, algae, and chloramines. A common guideline is to aim for 30 ppm of chlorine in the pool, and the amount of shock needed depends on the type of shock used. Here is a reference guide for increasing chlorine levels by ten ppm in a 10,000-gallon pool:

- Calcium Hypochlorite: 1.3 lbs
- Sodium Hypochlorite: 3.5 quarts
- Lithium Hypochlorite: 2.5 lbs
- Dichlor: 1.5 lbs

Before adding shock, ensure your water is properly balanced. High pH levels can render half of the shock inactive, so adjust the pH to around 7.2 for optimal effectiveness.

When shocking your pool, follow these steps for best results:

1. Clean the pool by removing debris from the floor and walls to avoid wasting the chlorine's power on dirt and debris.

2. Adjust the pH if it is high. Lowering the pH to around 7.2 ensures optimal chlorine effectiveness.

3. Check the labels of your pool shock products, as different shocks may require specific dosages or dilution in a bucket to prevent pool damage.

4. Add the shock to the pool while the pump is running, distributing it evenly across the water's surface. Avoid spilling shock on clothing or the pool deck. Add it slowly and close to the water's surface, preferably on a calm day to prevent wind from blowing it away.

5. Brush down the pool surfaces to help distribute the shock evenly and remove any dust or film accumulated. Perform thorough brushing, vacuuming, and backwashing after shocking.

If you need pool chemicals for shocking or any other pool care needs, contact Swimming Pool Discounters for assistance.

Note: The information provided here is for general guidance. It's important to follow the instructions on your pool shock products and consult with pool care professionals for specific recommendations based on your pool's size and condition.
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