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Pool shocks are essential pool maintenance chemicals that prevent bacterial and algae growth, balance chemical levels, and mitigate various contaminants. Factors like swimming pool size, usage, pool water quality, and location will determine the best pool shock for your situation.
In this review, we’ll look at today’s top-rated pool shocks, provide tips for figuring out what your pool requires, and answer some frequently asked questions.
Here are our recommendations
Top 5 Pool Shocks
- Best Overall: HTH Super Shock Treatment
- Best for Large Applications: NAZUHA Zappit Pool Shock
- Best Fast-Acting: DryTec Chlorine Shock Treatment
- Best Liquid: Austin’s Pool Tech Shock
- Best Water Clarifier: Robarb Super Blue Clarifier
Compare Top Pool Shocks
| Product | Quantity | Treatment Amount | Active Ingredients |
|---|---|---|---|
| HTH Super Shock Treatment | 12 one-pound bags | Treats 13,500 gallons per bag | Calcium hypochlorite |
| NAZUHA Zappit Pool Shock | 50-pound bucket | Treats 40,000 gallons per pound | Calcium hypochlorite |
| DryTec Chlorine Shock Treatment | 24 one-pound bags | Treats 10,000 gallons per pound | Calcium hypochlorite |
| Austin’s Pool Tech Shock | One-gallon jug | Not listed | Sodium hypochlorite |
| Robarb Super Blue Clarifier | 32-ounce bottle | Treats 5,000 gallons per ounce | Not listed |
| Product | Quantity | Treatment Amount | Active Ingredients |
Best Pool Shock Overall
HTH Super Shock Treatment
- $79.99
Prices taken at time of publishing.
Key Features
- Comes with 12 1-pound bags
- Treats 13,500 gallons of water per bag
- Uses calcium hypochlorite as the active ingredient
What Customers Are Saying
According to our research, customers liked the amount of pool shock that they got for the price. They also said that the product dispersed easily. However, those who didn’t care for this pool shock claimed it didn’t fully dissolve in their pool and occasionally leaked from the bag.
Best for Large Applications
NAZUHA Zappit Pool Shock
- $189.99
Prices taken at time of publishing.
Key Features
- Comes with a 50-pound bucket
- Treats 40,000 gallons of water per pound
- Uses calcium hypochlorite as the active ingredient
What Customers Are Saying
Satisfied customers we found liked how quickly this pool shock’s powerful formula treated their large pools. On the other hand, those who left negative reviews for this pool shock claimed it didn’t dissolve. Others struggled to open the bucket’s lid.
Best Fast-Acting Pool Shock
DryTec Chlorine Shock Treatment
- $110.99
Prices taken at time of publishing.
Key Features
- Comes with 24 1-pound bags
- Treats 10,000 gallons of water per pound
- Uses calcium hypochlorite as the active ingredient
What Customers Are Saying
Customers praised this pool shock formula, stating it was strong, fast-acting, and long-lasting. However, some customers we found did have to use multiple packages to treat their entire pool.
Best Liquid Pool Shock
Austin’s Pool Tech Shock
- $27.95
Prices taken at time of publishing.
Key Features
- Comes in a one-gallon jug
- Uses sodium hypochlorite as the active ingredient
What Customers Are Saying
Customers we found were impressed with how easy this pool shock was to use and how quickly it cleared debris from their pool. Others liked that it was tightly wrapped and did not leak out easily from the jug. On the other hand, some customers had issues with the weakness of the shock, claiming that it required at least a quarter of the bottle to work effectively. Several other customers also felt this product was overpriced for what it provided.
Best Water Clarifier
Robarb Super Blue Clarifier
- $49.99
Prices taken at time of publishing.
Key Features
- Comes with a 32-ounce bottle
- Treats 5,000 gallons of water per ounce
- Uses a non-toxic, non-irritating, biodegradable formula
What Customers Are Saying
Those who gave this product positive reviews said that it was able to clean even the dirtiest of pools. They also mentioned it working in pools of various sizes. However, we noted that dissatisfied customers thought that the formula was watery and the instructions were difficult to follow.
Buying Guide to Pool Shock
The type, amount, response time, and chemical makeup of pool shocks vary greatly. To find the best formula for your pool, consider the following factors.
Shock Type
Pool shock comes in liquid, granular, or tablet form and use one of three active ingredients to remove cloudy water:
Calcium Hypochlorite
This is the most common type of pool shock on the market. It’s strong and fast-dissolving, but it can damage vinyl pool linings.
Sodium Dichlor
This pool shock isn’t as strong. It slowly raises your pool’s pH, so you have to wait some time for it to dissolve before you can swim.
Potassium Monopersulfate
This non-chlorine shock removes bacteria and algae by oxidizing the water. You can use it when you don’t want to raise the available chlorine level of your pool.
Amount
Generally speaking, you need about one pound of pool shock per 10,000 gallons of water. Before you purchase pool shock, determine how much comes with the order. Some manufacturers sell pool shocks in bulk to reduce the number of orders you have to place during the swimming season.
Dissolve Speed
Pool shock comes in quick-dissolving and slow-dissolving formulas. If you need to use your pool shortly after shocking it, choose a quick-dissolve version.
Pool Type
Most pool shocks are designed for chlorinated indoor or outdoor pools. However, certain types of pools may require specialized pool shock. These types include:
- Fiberglass-lined pools
- Hot tubs and spas
- Saltwater pools
- Vinyl-liner and above-ground pools
Pool Shock Functions
All pool shock treatments will act on organic contaminants and encourage clear water. However, some specialize in certain functions. Common specializations include:
- Algae mitigation
- Bacteria removal and prevention
- Chloramine removal
- Improvement of free chlorine levels
- Balancing of pH levels
- Storm debris breakdown
- Water clarification and tone enhancement
- Winterization prep
Frequently Asked Questions About Pool Shock
Does pool shock contain chlorine?
Pool shock uses calcium hypochlorite, sodium dichlor, or potassium monopersulfate. Of these chemicals, only potassium monopersulfate is chlorine-free.
How often should I put pool shock in my pool?
For ideal pool care, shock your pool once a week during the active swimming season as well as at the beginning and end of the season.
You may wish to shock your pool following heavy rainstorms, as the added water can upset the chlorine balance.
You can also shock your pool if you notice that you have cloudy water or tinted green.
What does it mean if my pool shock is stabilized?
Stabilized pool shock contains a UV protection compound that prevents it from burning in the sun. Any pool shock with sodium dichlor is stabilized.
How We Selected the Best Pool Shock
To provide our readers with the best recommendations possible, we rely on several key sources of information to help guide our selection process.
Initial Research: Our research process began by generating a list of pool shock options with a significant number of verified-buyer reviews and an average customer review rating of 4–5 stars. We looked at positive and negative reviews alike, focusing on information from both satisfied and critical buyers.
Expert Insights: Through our years of experience, we’ve learned that listening to what others have to say is key to building accurate, well-rounded articles. To complement our in-house expertise, our team looked at reviews and videos from trusted publications and independent testers, spoke with subject matter experts, and drew insights from reader contributions.
Final Product Selection: We then began fine-tuning our list by replacing older models with the latest versions and eliminating any discontinued models. From there, we pared the list down further by comparing each model’s feature set and selecting the best-in-class options for various buyers, budgets, and scenarios.
Why You Can Trust Us
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Our team focuses on creating in-depth product and service review content. To date, we’ve published countless reviews of garden, lawn, and outdoor products—from fertilizer and garden hoses to patio furniture and snow blowers.
Once we conclude our research, we craft a comprehensive, user-friendly article of recommended products and additional information to help our readers make the right purchase.
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