Block chlorine lock with Cal Hypo

<strong>Block chlorine lock</strong> with Cal Hypo

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Goodbye chlorine lock, hello healthy pool water.

Only HTH fast-dissolving shock with Cal Hypo (calcium hypochlorite) clarifies and rids water of contaminants without using any CYA (cyanuric acid). That means you can prevent chlorine lock and get visibly brilliant pool water!

Cal Hypo

What is chlorine lock?

Many pool owners use stabilized chlorine-based shock and sanitizer products that contain CYA, or cyanuric acid. While chlorine will eventually burn off in the sun, CYA will not. So, when you add more stabilized chlorine to your pool, the CYA builds up, which causes overstabilization — otherwise known as chlorine lock.
Chlorine lock lowers the effectiveness of chlorine, which can result in:

● Algae infestation
● Contaminated pool water (germs/bacteria) that is unsafe for swimmers
● pH imbalances (which lead to high chlorine odor, cloudy water, red eyes and itchy skin)

The solution for chlorine lock? Draining your pool and rebalancing your water. Or, you can prevent it from happening in the first place with HTH™ Cal Hypo shocks and sanitizers.

shock Cal Hypo

Prevent chlorine lock with Cal Hypo

HTH Pool Care Chlorine Granules Ultra and HTH Pool Care Chlorine Skimmer Tabs contain Cal Hypo, not CYA, which means they are NOT stabilized. This makes them a great replacement for other chlorine products, such as Trichlor (TCCA), that contain CYA. HTH Cal Hypo shock and sanitizer products do not contain CYA, so they can never cause chlorine lock, but they will always provide visibly brilliant pool water.

Enjoy total peace of mind that your swimmers are safe, your pool water is healthy and maintenance is hassle-free.

Just look for the red Cal Hypo “no chlorine lock” icon on HTH products online and in stores.

As always, we’re here to help. If you have questions, contact our help line at 1-866-HTH-POOL or talk to our experts with our live chat!


Please read the following important reminders before adding pool chemicals to water:

• NEVER mix products together or dissolve before use.

• ONLY enter pool when FAC levels are below 4 ppm to prevent risk of bodily harm.