Select Page

Chlorine lock and chlorine demand can be a pesky problem for many pool owners. Beat the heat and have a crystal clear pool when you learn how to quickly and effectively diagnose and cure chlorine lock and chlorine demand. In this article, you will learn what chlorine lock and chlorine demand are, why they occur, and the best ways to prevent and cure them. You will learn the importance of pH and alkalinity levels, shock treatment, and stable sanitiser level to make sure your pool keeps its crystal clear look.

What is Chlorine Lock

Definition of Chlorine Lock

Chlorine lock is a phenomenon that occurs when pool owners add too much chlorine to the pool. This excessive amount of chlorine renders the sanitiser ineffective and prevents it from working as intended, resulting in poor pool water which can be cloudy and green and lead to the growth of algae, bacteria, and viruses. Chlorine lock is caused when the pH level in the pool is too low and the chlorine can’t perform its job properly.

Signs and Symptoms of Chlorine Lock

There are some immediate signs of chlorine lock that pool owners should be aware of such as cloudy, green, or smelly water, and the presence of algae, bacteria, and viruses. In the long term, chlorine lock can cause eye and skin irritation, and lead to other health issues if left untreated.

What Causes Chlorine Lock

The primary cause of chlorine lock is an imbalanced pH level and alkalinity. When chlorine is added to pool water that has a low pH level, it becomes ineffective, unable to perform its job to purify the water. In order to eliminate chlorine lock, pH must be regulated and alkalinity brought into balance.

What is Chlorine Demand

Definition of Chlorine Demand

Chlorine demand is when pool water contains foreign materials that absorb chlorine, such as bacteria, algae and other organic materials. Like chlorine lock, chlorine demand also renders sanitiser ineffective, leaving the pool with poor water quality and a cloudy, green appearance. Unlike chlorine lock however, chlorine demand can occur even when the pH and alkalinity levels are balanced.

Signs and Symptoms of Chlorine Demand

The signs of chlorine demand are similar to those of chlorine lock, such as cloudy and green water, the presence of algae and bacteria, and eye and skin irritation. In addition, the chlorine test results from pool water may be off, indicating the presence of foreign matter in the water.

What Causes Chlorine Demand

The cause of chlorine demand is usually an accumulation of organic matter in the pool water, such as dirt and oils. These materials can make chlorine levels rise and become ineffective, leading to poor water quality and build up of potential contaminants.

Curing Chlorine Lock

One of the most effective ways to cure chlorine lock is to shock the pool and maintain a proper level of chlorine. To do this, pool owners should first raise the pH level of the pool by adding soda ash or playing a liquid pH increaser. Then, add a shock treatment that chlorinates the water and kills bacteria and viruses, and maintain a stable chlorine level.

Curing Chlorine Demand

To cure chlorine demand, the first step is to balance the pH and alkalinity levels. Then, add a product such as chlorine shock or non-chlorine shock to the pool and stir it. This will help to destroy the bacteria, algae, and other organic materials that are causing the chlorine demand. Lastly, perform a deep clean to remove any dirt and debris from the pool, and use a product such as a clarifier to help further remove any organic matter.

People Also Ask

How Much Chlorine Should be Added to a Pool?

The amount of chlorine needed for a pool depends on the size of the pool, the amount of sunlight exposure, and the average number of people using the pool. The general rule is 3-5 parts per million (ppm) of chlorine should be added per week.

How Long Does it Take to Fix Chlorine Lock?

It can take up to one week to fix chlorine lock. Maintaining correct pH levels, shock treating the pool, and properly adding chlorine is important to be sure the pool is free of contaminants.

Does Chlorine Lock Damage Pool Equipment?

Chlorine lock can damage pool equipment if it is not addressed quickly. Deposits of contaminants, such as algae and bacteria, can form in plumbing, causing the equipment to run inefficiently or breakdown completely.

Can Chlorine Lock Make you Sick?

Yes, chlorine lock can make you sick. Ingesting contaminated pool water can cause vomiting and diarrhea, skin irritations, eye hurt, and other health issues. It is important to ensure chlorine lock is cured properly as soon as possible.

Final Words

Chlorine lock and chlorine demand can lead to poor pool water quality, irritation, and other health risks if left untreated. Knowing how to recognize the signs, diagnose the problem and cure it properly is important for all pool owners. Make sure the pH levels are balanced, and the pool is shock treated with a proper level of chlorine each week. With proper maintenance, pool owners can prevent and cure chlorine lock and demand, leaving their pool clean and crystal clear all swimming season long.