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Why does my pool have no free chlorine?

4 min read

Asked by: Ashley Jackson

You might have an infestation of algae, fungus or bacteria that can deplete normal chlorine levels and it is possible for this to occur without many visible signs. Your pool may appear to have a dusty look on the pool bottom. If you brush it and it clouds the water, then it is most likely a Mustard Algae.

How do I raise the free chlorine in my pool?


At a higher have your chlorine at a higher level to be effective. So if you have cyanuric acid over 100 parts per million to be effective.

What does no free chlorine mean?

Free chlorine refers to the amount of chlorine that has yet to combine with chlorinated water to effectively sanitize contaminants, which means that this chlorine is free to get rid of harmful microorganisms in the water of your swimming pool.

What do I do if my free chlorine is low?

If your total chlorine level is high, you will use a non-chlorine shock; if it is low, you will use a chlorinated shock. As a rule, you will need to raise free chlorine to 10 times your combined chlorine to hit what is known as “break point.” Therefore, it is good to deal with combined chlorine while it is still small.

Will Shock raise free chlorine?

“Shocking” refers to the process of adding chlorine or non-chlorine pool chemicals to the water in order to raise the “free chlorine” level. The goal is to raise this level to a point where contaminants such as algae, chloramines and bacteria are destroyed.

Does chlorine free shock raise free chlorine?

That said, it should be noted that non-chlorine shocks don’t kill algae, or raise the chlorine level. Your FAC level should be around 1.5 ppm for a non-chlorine shock to work effectively.

How much shock Do I need to raise free chlorine?

roughly 10 times

The goal of shocking your pool is to raise the free chlorine level of your pool water to roughly 10 times the combined chlorine level of your pool water.

How do you balance free chlorine and total chlorine?

Subtract the free chlorine measurement from the total chlorine measurement to calculate the amount of combined chlorine (total – free = combined). If combined chlorine is higher than 0.5 ppm you should shock the pool. Depending on the total chlorine level, use either a non-chlorine shock or a chlorinated shock.

Why does my pool lose chlorine so fast?

If your water’s pH is too high, it hinders the chlorine’s ability to efficiently clean the pool. A water pH level that is too low causes the chlorine to dissipate more quickly. Therefore you’ll need to add more chlorine to accomplish the task.

What happens if you put too much shock in a pool?

Although, if you overdo the shock treatment, you risk getting green hair from chlorine due to the excess chlorine oxidizing the copper in the water. You can execute a shock treatment with a few different types of pool shock, just be mindful of how much you’re using.

What is more important free chlorine or total chlorine?

In order for your pool to be properly sanitized, the free chlorine level must remain higher than the combined chlorine level. This is why it’s so important to test your pool water regularly. This is easy to do with test strips or a liquid test kit.

Should I backwash after shocking pool?

Steps for Preventing Algae



If your pool is used frequently, shock it at least once a week. Clean or backwash your filter regularly. Run your pool pump for at least 10 hours per day to completely circulate the water.

Do you run filter when shocking pool?

Run the filtration system



While shocking your pool will help kill any germs any algae, it won’t actually get rid of them; for that, you need your filter. So be sure to run your pool filter for at least 24 hours.

Is liquid shock better than powder?

Both liquid and powder shocks contain the same active chemical used for pool sanitation, but their usage and strength are different. Other than coming in a different form, liquid chlorine is also more budget-friendly and unstabilized. On the other hand, powder shock is easy to stabilize, and its solid form dissolves.