Get long-lasting protection from extreme algae. Our strongest, non-foaming algae control kills blooms and prevents regrowth for up to 3 months.

Long-lasting algae eliminator
Kills and prevents all algae types
Swim immediately
Compatible with all swimming pools
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Our strongest algae control
Kills, prevents and protects against regrowth of heavy green, black and mustard swimming pool algae for up to 3 months.

Non-foaming, fast-acting
Add HTH® Algae Guard Ultra directly to your swimming pool water and swim right away!

Compatible with all pools
This non-staining formula is great for all swimming pools including vinyl-lined and salt water systems.

You’re all clear with HTH®
For best results, use HTH® Algae Guard Ultra every 3 months. Works great with HTH® Shock products.