HTH® Ultimate Algae Guard

HTH® Ultimate Algae Guard, 1 quart is a long-lasting, non-foaming algaecide product that prevents and kills green and yellow algae. 


About This Item

HTH® Ultimate Algae Guard is the strongest algaecide formula available from the brand pool owners have trusted for over 25 years. Ultimate Algae Guard both kills and prevents even the ost stubborn green, black and mustard algae. This non-foaming algae guard treats pool water for up to 90 days after applying to your pool – and you can swim just 15 minutes after use.

  • Kills and prevents all algae
  • Non-foaming
  • Prevents algae growth for up to 3 months
  • Non-staining formula
  • Swim immediately
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Stop Algae Growth with HTH® Ultimate Algae Guard

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Works Quickly

The HTH® Ultimate Algae Guard quickly kills and prevents green algae so you can get back to swimming as soon as possible. Use regularly for maximum effectiveness.

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Concentrated Formula

Just 4 fl. oz. works in 10,000 gallons of water to kill algae spores and prevent regrowth. Plus, it's compatible with chlorine, bromine, and salt water systems.

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Easy to Use

Simply add the product directly to the pool in several places with the pump running. Keep the pump running for several hours. Wait 15 minutes before entering the pool.

How to Prevent Algae Growth in Swimming Pools

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Brush & Remove Debris

To prevent algae growth, brush your pool weekly to remove any spores that have attached to the walls or steps. Trees and plants are a common source of algae spores, so trim leaves and branches back as much as possible and remove leaves and other debris from your pool right away. 

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Clean Your Filter

Clean your filter regularly to effectively remove dead algae spores from your pool. Use HTH® Filter Cleaner to clean all filter types and help the filtration system to work more efficiently.

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Add Chemicals

Shock your pool weekly to boost chlorine levels and keep your water crystal clear. One of the best ways to protect your pool from algae is to use a regular shock treatment, then follow up with a weekly dose of an algaecide like HTH® Ultimate Algae Guard.




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