5 Best Pool Shocks of 2021

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Best Pool Shock

At some point, you will need to shock your pool to get rid of chloramines, clear the water or kill algae and bacteria. For this, you need to make sure you get the best pool shock because not just any will work for you.

Pool shock comes in various types and forms. Additionally, they will also differ in other things like the available chlorine and the dissolving speed.

In this guide, we explain the crucial factors you need to consider when choosing a pool shock and review a few of the best options out there.

5 Best Pool Shocks - Review

IMAGE

PRODUCT

FEATURES

In The Swim Chlorine Pool Shock

1. In The Swim Chlorine Pool Shock (Best Overall)

  • Powerful shock with 65% available chlorine
  • Fast-action formula
  • Quick dissolving
Clorox Pool&Spa 33506CLX Pool Shock

2. Clorox Pool&Spa 33506CLX Pool Shock (Best for the Money)

  • Good bargain for a multifunctional 6-in-1 shock
  • Swim ready in just 15 minutes
  • Zero impact on pH
Doheny's Chlorine Super Shock

3. Doheny's Chlorine Super Shock

  • At least 65% available chlorine
  • 1 pound treats 10,000 gallons
  • Kills algae, bacteria & other contaminants
DryTec 1-1901-24 Calcium Hypochlorite Chlorine Shock Treatment

4. DryTec 1-1901-24 Calcium Hypochlorite Chlorine Shock Treatment

  • Fast-acting formula
  • Quick & complete dissolving
  • Low dosage required
HTH 52028 Ultimate Shock Treatment

5. HTH 52028 Ultimate Shock Treatment

  • Multifunctional shock treatment
  • 1 bag treats up to 13,500 gallons
  • Turns blue to indicate its working

PRODUCT

1. In The Swim Chlorine Pool Shock

(Best Overall)

In The Swim Chlorine Pool Shock
  • Powerful shock with 65% available chlorine
  • Fast-action formula
  • Quick dissolving

2. Clorox Pool&Spa 33506CLX Pool Shock

(Best for the Money)

Clorox Pool&Spa 33506CLX Pool Shock
  • Good bargain for a multifunctional 6-in-1 shock
  • Swim ready in just 15 minutes
  • Zero impact on pH

3. Doheny's Chlorine Super Shock

Doheny's Chlorine Super Shock
  • At least 65% available chlorine
  • 1 pound treats 10,000 gallons
  • Kills algae, bacteria & other contaminants

4. DryTec 1-1901-24 Calcium Hypochlorite Chlorine Shock Treatment

DryTec 1-1901-24 Calcium Hypochlorite Chlorine Shock Treatment
  • Fast-acting formula
  • Quick & complete dissolving
  • Low dosage required

5. HTH 52028 Ultimate Shock Treatment

HTH 52028 Ultimate Shock Treatment
  • Multifunctional shock treatment
  • 1 bag treats up to 13,500 gallons
  • Turns blue to indicate its working
In The Swim Chlorine Pool Shock

In The Swim Chlorine Pool Shock is our best overall pool shock as it is fast-acting, quick-dissolving, and removes most types of pool water contaminants.

The pool shock contains up to 65% available chlorine, making it fast acting as it quickly raises the chlorine levels in the water. The high chlorine level also means a little of it goes a long way, and therefore just 1 pound is enough to shock 10,000 gallons of water.

Also, the formula is fast-dissolving, and you can add it directly to the pool without having to pre-dissolve. By adding this pool shock to your pool, you can quickly kill bacteria and control algae, and it will also get rid of most organic contaminants in the water.

This pool shock can be pretty harsh on vinyl liners. However, this should not be an issue if you dissolve it in the pool fast to ensure it does not get enough time to bleach the liner.

Pros

  • High enough level of free chlorine
  • Destroys organic contaminants
  • Raises chlorine levels super-fast
  • Dissolves fast and can be added directly to pool

Cons

  • Can be harsh on vinyl liners
Clorox Pool&Spa 33506CLX Pool Shock

The Clorox Pool&Spa 33506CLX Pool Shock is a multifunctional 6-in-1 pool shock that comes at a more affordable price tag to ensure you get the best value for money.

With the multifunctional formula, the pool shock will help kill all kinds of contaminants and improve overall water quality. Adding the shock will kill bacteria and all types of algae while also eliminating the pungent chlorine odor.

This pool shock will also help improve the filter performance by destroying contaminants, and hence you end up with crystal clear water.

Additionally, the shock will not affect your pool pH, and its fast-dissolving formula will make the pool safe for a swim in just 15 minutes to minimize downtimes.

The instructions are not very clear in some sections, such as the dosage. However, this pool shock is still easy to figure out even with the inferior instructions.

Pros

  • Great value for money
  • Minimal pool downtime
  • Does not affect the pool pH
  • Improves filter performance

Cons

  • Not the best instructions
Doheny's Chlorine Super Shock

Doheny's Chlorine Super Shock is a 68% calcium hypochlorite pool shock with at least 65% available chlorine that is more than enough to shock your pool water fast. 

Adding this shock to your water will eliminate bacteria, all kinds of algae, and organic contaminants to leave your pool clean and clear.

A little of this pool shock goes a long way, as just 1 pound is enough to treat 10,000 gallons of water. Better still, it comes at a more affordable price tag to make shocking your pool even cheaper.

While this pool shock does not seem to dissolve fast enough, this is an easy problem to work around by pre-dissolving it in a large bucker before adding it to the pool. Also, it can make the pool water a little cloudy, but it should clear up within a short time.

Pros

  • Contains a high amount of available chlorine
  • A little of it goes a long way
  • Eliminates all kinds of pool contaminants
  • Relatively more affordable

Cons

  • Slow dissolving
  • Can make the water a little cloudy
DryTec 1-1901-24 Calcium Hypochlorite Chlorine Shock Treatment

The DryTec 1-1901-24 is a fast-acting chlorine shock treatment that will help keep your pool in great shape. It will kill bacteria, algae, and all kinds of organic pool contaminants in the pool quickly.

With this pool shock you will get at least 65% available chlorine, meaning you can shock the pool without having to add too much of the pool shock. Just 1 pound of the shock is enough to treat 10,000 gallons of pool water.

This pool shock dissolves fast in the water and will not leave any residue behind. Therefore, you can even add it to the pool directly without having to pre-dissolve.

The only gripes with this pool shock are that it makes the water a little cloudy and is a little expensive. However, it should clear up within a few hours, and vacuuming can also speed up the process. Also, it is worth the extra bucks as it does a fantastic job.

Pros

  • Acts super-fast
  • Dissolves quickly and completely
  • Contains high available chlorine
  • Requires a low dosage

Cons

  • Makes water cloudy
  • A little expensive
HTH 52028 Ultimate Shock Treatment

HTH 52028 Ultimate Shock Treatment is a multifunctional pool shock that will give your water complete treatment. It kills bacteria and algae, clarifies and softens the water, and helps prevent scale formation.

You can use this pool shock on all swimming pool types, including vinyl and gunite finishes and those with saltwater sanitation systems.

The pool shock has a more potent formula that ensures you will not need to use a lot of it. Just 1 bag is enough to treat up to 13,500 gallons of water. Also, you can quickly tell when the shock is working as it will change the color to blue.

This pool shock is a little pricier compared to most others on our pool shock review. However, it is worth it for a potent and multifunctional product that will leave your water in great shape.

Pros

  • Formula offers complete pool water treatment
  • Color changes to show it is working
  • Compatible with any swimming pool type
  • One bag treats more water

Cons

  • A little pricier

How to Buy the Best Pool Shock

How to Buy the Best Pool Shock

1. Pool Shock Types

Pool shock comes in three different types: sodium dichlor, calcium hypochlorite, and potassium monopersulfate. Each of these types will be ideal for different kinds of pools and situations.

Sodium Dichlor

Sodium dichlor or sodium dichloro-s-triazinetrione is stabilized pool shock type, meaning it includes cyanuric acid to prevent UV degradation. Therefore, sodium dichlor is the most ideal for outdoor swimming pools that face regular exposure to a lot of sunlight.

This pool shock will not add any calcium to your pool water and is hence also ideal for pool owners who struggle with hard water. What's more, sodium dichlor has around 56% strength, more neutral pH, and when you add it to the water, it will be safe to swim in as little as 15 minutes.

However, sodium dichlor can be pretty harsh and hence will bleach delicate pool surfaces like vinyl. Also, it is more expensive than calcium hypochlorite.

Calcium Hypochlorite

Calcium hypochlorite or cal hypo is the most common pool shock type. Typically, it has a strength of between 50% and 70%.

The shock can be highly effective against organic contaminants, bacteria, algae, and chloramines. Also, it is the most affordable pool shock option.

For the downsides, cal hypo tends to be quite harsh and will hence damage delicate pool surfaces. Also, you have to wait for up to 48 hours before using the swimming pool after adding the shock.

Potassium Monopersulfate

Potassium monopersulfate or non-chlorine shock provides an alternative for pool owners that do not want to use chlorine-based shocks.

The absence of chlorine makes this shock ideal for pools that uses non-chlorine sanitizers like bromine pools. This shock will not be affected by the sunlight, and it works by oxidizing the impurities and chloramines in the water.

The non-chlorine shock will not add cyanuric acid or calcium to the water. However, this shock type is less effective against algae, bacteria, and some types of organic contaminants.

2. Available Chlorine

Shocking a pool requires you to add a higher dose of chlorine than you would typically do. Therefore, when choosing a pool shock, the amount of available chlorine is crucial as it determines how much of it you need to use to get the chlorine levels to the required level.

The type of pool shock you choose is one of the main determinants of the available chlorine. However, most options out there will have between 40% and 80% available chlorine

Therefore, something with 68% available chlorine like the Clorox Pool&Spa 33506CLX Pool Shock will be fantastic.

3. Form (Liquid, Tablet, Granular, Powder)

You can get pool shock in either liquid, granular, or powder form. The form affects the ease of use and therefore, it is a crucial factor to consider when shopping.

Liquid pool shock is the most convenient as you only need to pour it directly into the pool. Since the liquid will not require any dissolving, it will spread much faster in the swimming pool, meaning you get a shorter pool downtime.

Granular and powder pool shock often require dissolving in water before use, meaning more work for you, and will require up to 48 hours before the pool is safe for use. On the other hand, table pool shocks have the slowest application as one can take up to 2 hours to dissolve.

4. Dissolve Speed

Any pool shock you choose needs to dissolve fast to ensure you do not have to wait long before the pool is safe to use again.

Therefore, before settling on any pool shock, it is crucial to check the specific dissolve speed on the labeling or read customer reviews to find out if it dissolves fast enough.

5. Additives Free

Some pool shocks will include additives, which can affect your pool chemistry. For example, calcium hypochlorite can make your water hard by adding a lot of calcium, while sodium dichlor can raise cyanuric acid levels.

If you do not want to affect your pool's chemistry, it is always better to go for an additive-free pool shock. Even if it is hard to get a pool shock with zero additives, look for something that does not have any unnecessary compounds.

Bottom Line 

With the best pool shock, you can quickly get rid of chloramines, kill bacteria and algae and keep your swimming pool clear.

Regardless of the pool type you have, there is a good shock option on our list. However, In The Swim Chlorine Pool Shock is our top overall recommendation as it is a multifunctional and powerful shock that acts fast.

On the other hand, if you are looking for something that will give you the best value for money, the Clorox Pool&Spa 33506CLX Pool Shock is our recommendation.