Why is my pool water still green after shocking?

If your pool water is still green after shocking, there could be several reasons for this issue. Shocking the pool is a process of adding a large dose of chlorine to kill algae, bacteria, and remove other contaminants. Here are some potential reasons why your pool water is still green:

Insufficient shock treatment:

You may not have added enough shock to the pool. Follow the manufacturer’s instructions on the shock product you are using, and make sure to add the appropriate amount based on your pool size.

Organic debris:

If there is a significant amount of organic debris in the pool, such as leaves or grass, it can consume chlorine and hinder its effectiveness. Remove any debris from the pool and continue with shock treatments.

If you still can’t see the bottom after shocking your pool, you may need to add a clarifier or flocculant the next day to remove the dead algae.

Flocculant binds to small particle impurities in the water, causing them to clump together and fall to the bottom of the pool. On the other hand, Clarifier is a maintenance product used to restore shine to slightly cloudy water. They both bind microparticles into larger particles. However, the particles created by clarifiers are removed by the filtration system, whereas flocculants require extra time and effort to vacuum particles that have dropped to the pool floor.

Poor circulation and filtration:

Inadequate circulation and filtration can hinder the distribution of the shock throughout the pool. Ensure that your pump and filter are working correctly, and run them for an extended period to help clear the water.

Your CYA (Cyanuric Acid) or pH level is too high

Chlorine stabilizer (Cyanuric Acid) protects chlorine in the pool from the sun’s UV rays. UV light destroys or degrades unstabilised chlorine, thus making chlorine a lot less effective. To fix this, you want to make sure your CYA level is not higher than 100 ppm before you add your pool shock. If the cyanuric acid level is a little hight (50-100 ppm), raise the dosage of chlorine for shock.

There’s a similar relationship between the efficacy of chlorine and the pH level of your pool. Remember to test and adjust your pH level to 7.2-7.6 before shocking your pool.

Presence of metals:

Pools can immediately turn green after being shocked when they have metals like copper in the water. These metals oxidise when exposed to high levels of chlorine, which makes the pool water turn green. If your pool has metal issues, consider using a metal sequestrant to decolor and prevent staining.

If you’ve already tried shocking the pool and the water remains green, consider consulting with a pool professional or water chemistry expert to diagnose the specific issue and determine the best course of action for your particular situation.