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HTH

HTH 67289 Swimming Pool Care Algae Guard Ultra, Swimming Pool Chemical, Long Lasting Formula, 32 fl oz

  • Based on 1,860 reviews
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Availability: In Stock.
Fulfilled by Amazon
Arrives May 7 – May 19
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Style: Ultra Algaecide


Features

  • BENEFIT: Get long-lasting protection from extreme algae; This non-foaming algae control kills and prevents blooms of all algae types
  • 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 saltwater systems
  • YOU'RE ALL CLEAR WITH HTH: For best results, use HTH Algae Guard Ultra every 3 months; Works great with HTH Shock products

Description

Get long-lasting protection from extreme algae. Our strongest, non-foaming algae control kills blooms and prevents regrowth for up to 3 months. HTH Algae Guard Ultra is HTH's strongest algae control. It kills, prevents and protects against regrowth of heavy green, black and mustard swimming pool algae for up to 3 months. Its compatible with all pools. The non-staining formula is great for all swimming pools including vinyl-lined and salt water systems. It non- foaming and fast-acting formula means you can add HTH Algae Guard Ultra directly to your swimming pool water and swim right away! For best results, use HTH Algae Guard Ultra every 3 months in combination with other HTH products like HTH shock and HTH chlorine tablets.

Brand: HTH


Item Form: Liquid


Product Benefits: Controls Algae, Maintains Clean Sanitized Water


UPC:


Number of Items: 1


Brand Name: HTH


UPC: 073187672896


Item Type Name: Algaecide


Included Components: HTH 67289 Swimming Pool Care Algae Guard Ultra, Swimming Pool Chemical, Long Lasting Formula, 32 fl oz


Manufacturer: Innovative Water Care


Unit Count: 32.0 Fluid Ounces


Manufacturer Warranty Description: Warranty


Item Form: Liquid


Product Benefits: Controls Algae, Maintains Clean Sanitized Water


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: May 7 – May 19

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Top Amazon Reviews

    • As far as I can tell this stuff really works to prevent algae growth.
Style: Advanced Algaecide
When we put our pool up many years ago we didn't have any great options that kept it away from trees. I had to either deal with the leaves falling off the trees into the pool or cut the trees down. I was not going to cut the trees down. Every year it seems I am having to deal with at least two outbreaks of algae growth in the pool, possibly due to the leaves falling into the pool. Before I opened the pool this year I did some research on preventing algae. What I found was make sure the pool water is stabilized, chlorine level is always kept at the proper level and all other required chemicals are kept at their proper level. I've been doing that every year but still got algae. This year I decided to use an algaecide along with regular chemical maintenance. I followed the instructions for initial treatment for my pool size and added that amount. I'm also adding 2 ounces to my 15,000 gallon pool every 5 days. A bit more than recommended, but to date I have not had any algae problems. And now that I said that I'll probably have an issue. :-) But it's getting late in the season for where I live, we close the pool right after labor day, and so far no issues with algae. I'm going to attribute my lack of algae growth to this product. The addition of this algaecide is the only thing that's changed from previous years when I was having an algae problem. And it's been hot this year and heat typically aids in algae growth. Product seems to be working well for me. It's worth a shot if you have algae issues. ... show more
Reviewed in the United States on August 15, 2025 by JSF
    • Good product
Style: Advanced Algaecide
Good price
Reviewed in the United States on March 23, 2026 by Randy
    • This stuff works well
Style: Advanced Algaecide
Have used this on my inground pool during summer months when I have problems w green algae. Clears the pool pretty fast. It does on occasion leave bubbles on surface for a day or 2 so recommend not using pool for 24 to 48 hrs. But it does clear the pool of algae
Reviewed in the United States on November 25, 2025 by Bob Bojorquez
    • Shipping not the best
Style: Advanced Algaecide
This stuff is amazing, totally clears up my pool. Only complaint I have is the delivery, was suppose to have in 2 days! I ordered on 10/25 Didn’t receive until 11/5!
Reviewed in the United States on November 10, 2025 by Lara Peterson
    • Fantastic.
Style: Advanced Algaecide
Review Image by David
Review Image by David
I'm located in FL and would constantly fight issues with my inground pool for the last 2 years. Daily I'd vacuum the floor and walls, change my filter for one that would get soaked overnight in muriatic acid and power washed the next day before the swap. Always green if I skip a day. This first picture isn't even at its worst. After using this brand shock as well as this product, chlorine at 4ppm and I use Arm and Hammer Clear Balance tabs. After 24 hours of shock with pump running, added this product and clear balance tabs, brushed and vacuumed walls and floor, water was cloudy and foamy, so follow directions to a T because anymore and I'd have probably had sludge build up. After 48 hours, nothing was growing back on the walls or floor, and 72 hours later, my water was crystal clear and still no growth anywhere. Of course still changed filter between all this. Second photo is now a week later, last night before this picture I added the maintenance dose. Every time I've pulled the filter it has way less discoloration and now I'm going to change it every 2-3 days and see what happens. Great product. Easy to use. Visual and fast results. Just follow instructions. ... show more
Reviewed in the United States on June 27, 2023 by David
    • Amazing product!
Style: Ultra Algaecide
Review Image by Punkin's Mommy
Review Image by Punkin's Mommy
Review Image by Punkin's Mommy
This product is amazing! My pool has never been this blue. We recently had a tropical storm come through our area dumping massive amounts of rain which caused an ugly mustard algae bloom. I must have dumped 5 gallons of chlorine into it over the course of a week and the algae wouldn't budge - it actually got worse. In desperation, I ordered this product. We put 14 fluid ounces in immediately. It lightened up the pool, but there was still some algae present, so we added the rest of the 32 ounce bottle the next day. Overnight the algae disappeared and the pool got even bluer as time went on.There is currently no chlorine left in the pool and it is still blue with no signs of algae. I put the last of the product in on Monday and today is Friday. This product works miracles. I wish I had known about it sooner as I could have saved myself a ton of money and grief. Other users have mentioned having trouble with foam. We have had zero foam. The only thing I can think is maybe the product is interacting with other chemicals present in their water, because we have had no foam and we used the whole bottle. Excellent product. I highly recommend for stubborn algae problems. ... show more
Reviewed in the United States on August 16, 2024 by Punkin's Mommy
    • It Works
Style: Advanced Algaecide
There are many resources on the Internet claiming that yellow mustard algae can be eradicated simply with high dose shock treatments, but in my experience this never works and is a huge waste of time and money. This product works. I add a small amount once a week and have seen no trace of the algae since. I'll continue to use it. ... show more
Reviewed in the United States on August 16, 2025 by stubee5150
    • Product worked great!
Style: Advanced Algaecide
Crystal blue pool but noticed a few stubborn black algae spots show up. Tried a couple different products with no results. Algae got worse. Had to use the whole bottle, two different treatments a couple days apart but it worked perfectly. Now I can finish getting the pool swim ready.
Reviewed in the United States on July 21, 2025 by Jeanifer C.

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