How Many Chlorine Tablets Per Week Is Ideal For Your Pool?

The swimming pool is fun but it comes at a price of sacrifice and adequate knowledge of how it operates for efficiency. The chlorine content in a swimming pool is directly proportional to how best maintenance and water condition systems have been monitored.


How Many Chlorine Tablets Per Week

In cases where there are misbalances in the chlorine chemical content of the swimming pool, swimmers are vulnerable to a lot of health and infection issues. Some conditions are worse to the extent the swimming pool becomes malodorous, repulsive, or totally green, signifying massive colonies of algae.

To suppress these, there are different forms of chlorine addition mechanisms put in place chlorine tablets happen to be one of the popular quick, and effective ones.


How Many Chlorine Tablets Per Week?

Now, the questions come, “How many chlorine tablets per week should I use in my swimming pool?” First, you have to determine the level of chlorine in your swimming pool.

This will push you towards maybe chlorine tablets will be efficient (around 2 – 4ppm) or you need an immediate pool shocking if it is below 2 ppm. The pool’s water volume and the roles of environmental contributions like rain, storm, or human activities have to be considered.

For commercial swimming pools, chlorine tablets are used every day and for every 5000 gallons of water, 1 chlorine tablet is enough to have a significant impact.


The volume of the swimming pool (gallons) = length × width × average depth × multiplier.


  • The pool is 20 feet by 40 feet
  • The pool is rectangular
  • The shallow depth and deep depths are 4 feet and 6 feet respectively


Length × width = 20 × 40 = 800

Multiplier will be 7.5 for rectangular but if round, 5.9

Average depth = (shallow depth + deep depth)/2 = (4 + 6)/2 = 10/2 = 5 feet

Then volume of swimming pool = 800 × 7.5 × 5 = 30,000 gallons.


Just input your swimming pool figures and get your volume with this illustration.

For this volume, 30000 gallons, the number of tablets to be used will be 30000 ÷ 5000 = 6 tablets at once.

Before the introduction of chlorine tablets, you should be able to calculate the amount needed for your swimming pool with the provided information and have basic knowledge on basic things like the effect you should expect from the chlorine tablets, the type of chlorine tablets, and their constituents when to add chlorine tablet, methodologies involved in adding them, when you can start to swim after chlorine tablet application, an alternative to chlorine tablets and a quick overview of how long can chlorine tablets sustain your swimming pool before you introduce another. This is what this article contains. Let’s proceed.


Read: How Much Chlorine To Add To Pool First Time?


Chlorine Tablet From An Overview Angle

Chlorine tablets are chemically bonded molecules of chlorine that when dissolved in water release the chlorine content contained into the water whilst changing the chemical balance of the water in favor of chlorine constituents.

They exist in circular or nugget-shaped forms and are about three inches thick on average. Some products exist in one or two inches depending on their concentration of chlorine.

Chlorine tablets are easy to use, quick to act, and among the commonest form of chlorine regulation. With an increased demand for chlorine tablets for their enhanced ability, there were records of shortages in the supply of them.

Although the stay-at-home structure of Coronavirus and the chemical fire outbreak in one of the three largest suppliers of chlorine contributed to the shortage, as chlorine tablets’ popularity increased and swimming pool owners discover it is much better, the more they demand it.


What Effect Will Chlorine Tablets Bring To My Swimming Pool?

clean pool

The dissolution of chlorine tablet reacts in the swimming pool like every other chlorine-based chemical like liquid chlorine, granular chlorine, and direct pool shock. The swimming pool will experience an active clearance of bacteria, algae, and bathers present in the pool’s water.

Chloramines, products formed from the reaction of nitrate and excessive chlorine, which are toxic to swimmers are reduced back to use chlorine for the swimming pool usage.


Chlorine tablets disinfect the swimming pool and bleach off the surface of the pool to have a clear surface. When maintenance procedures are stopped for some days, there should be a cloudy or stinking swimming pool to be left with. If that is your case, you can clear this up with the addition of an adequate level of chlorine.

If your swimming chlorine level goes below the normal level, 2 – 3 ppm, chlorine tablets can bring about a balance when added. In environments with exposure to heavy rainfall, dirt from trees, storms, or a little waterflood, a chlorine tablet is a quick solution to striking a balance in their water condition.

Chemical Balancing

Vomits, cosmetic release, feces, urine, and other human waste contributions in the swimming pool will distort the chemical balances and set up the introduction of bacteria or pathogens. Chlorine tablets will work in the case by making the chemical balance right, the bacteria or waste contributed neutralized and the color of the swimming pool clear.

In summary, they bring about a change in chlorine level to match the situation at hand, produce cyanuric acid during the processes (cyanuric acid protects the swimming pool’s surface from ultraviolet rays), and, clear off bacteria, algae, and pathogens.

If chlorine tablets are too much in a swimming pool, they also pose health issues like skin irritation, infections, and diarrhea depending on how high the chlorine level is.


Read: How Many Chlorine Tablets For 10ft Pool?


Type of chlorine tablet and chemical constituents

Chlorine tablets are composed mainly of trichloro-s-triazinetrione (Trichlor) or dichloro-s-triazinetrione (Dichlor).

Both are acidic in nature and general chlorine tablets come in a pH of 2.9 creating noticeable differences in the total pH of the swimming pool aside from the chlorine contribution.

Chlorine tablets exist in two forms:

  • Stabilized chlorine tablets: This type of chlorine tablet contain cyanuric acid of up to 52% by weight. These chlorine tablets are targeted at maintaining the chlorine balance gotten by the chlorine content through the protection from sunlight, ultraviolet rays, quick evaporation, and other intruding airborne influences.
  • Unstabilized chlorine tablets: With an average of 75% chlorine content, unstabilized chlorine tablets contain no added cyanuric acid. The other contents in them are slight algaecides and pool clarifiers which are also needed in the swimming pool in the long run.


All chlorine tablets manufacturers have distinctive features they bring on for their products which will be indicated in the manual of the pack.

Be patient enough to read through the instructions and the suitability of their chlorine tablets in the swimming pool but usually in a 4 ounces chlorine tablet, you should expect 2.6 chlorine content which is considerately good enough for the impact needed per gallon.

Stabilized chlorine tablets are usually more expensive than unstabilized ones. If your pool is an indoor one and not exposed to sunlight, you should go for the unstabilized ones.

If outdoor, stabilized ones are your best fit unless you want the chlorine content in your swimming pool to be drained off by evaporation, or distorted by the sunlight during the day.


When To Add Chlorine Tablet To The Swimming Pool

A Series of events can lead to the need to add chlorine tablets to the swimming pool. While many swimming pool owners add chlorine tablets even without any sign of deficiency, and just for preventing the forthcoming of any issue, the following are conditions that show there is a need to add chlorine tablets to a swimming pool:

  • When the chlorine level is near zero: A very low level of chlorine requires a fast solution to first stabilize the chemical proportion before any further treatment.
  • The pH is very high: High alkalinity fosters the growth of bacteria, algae, and pathogens. In cases where the alkalinity is high, the swimming pool will turn into a favorable environment for the growth of these unwanted entities.
  • Green colored water: The presence of algae is noticeable with their prevailing appearances in green, black, yellow, or even pink color. They exist when the water’s chemical condition supports them which will never happen if there is adequate chlorine in the swimming pool.
  • Odorous water: When you start to feel repulsed by the smell of your swimming pool, it is time to add chlorine tablets for disinfection and cleaning the surface.
  • After a storm or excessive swimming timespan: Storms and rainfall facilitate random particles movements and your swimming pool wouldn’t be an exception for receiving these particles. You might have twigs, debris, leaves, or any sort of particles thrown into your pool. If this happens, test the chlorine level first to confirm if the event affects your chemical balances and do the needful.


If you are simply asking for the best time to add chlorine tablets to your swimming pool, it is however advised to be added after filtration and at sunset.

This will give it more time to react with the water without the intervention of the sun. This is applicable whether you are using stabilized chlorine tablets or any unstabilized ones.


Read: How Much Chlorine For 1000 Gallon Pool? (Quick Answer)


How To Add Chlorine Tablet In The Swimming Pool

Swimming conditions like hardness, pH, cyanuric acid, alkalinity, and others are affected by chlorine tablets, so if you are to apply them, they must be fully saturated in the whole volume of the water and not just concentrated in one part. This will distort the chemical balance and make the application ineffective.

There are different ways you can add chlorine tablets to your swimming pool depending on your facilities and your conveniences.

1. Using a floating dispenser:

floating dispenser

A floating dispenser is a simple mechanism that you can use to evenly spread a material you wish to dissolve in the swimming pool with ease. In the absence of a floating dispenser, you can easily get one in your local swimming pool or home utensils store.

With that, you can simply open its canister, put in the tablets, and close it back. Place the floating dispenser on the pool and watch as it skates through the surface gently.

If you notice it stays in one position, use a paddle to put it into motion. Staying in one place will enhance much concentration in that spot, causes imbalances, and stain the wall of the spot.

Read: Can You Leave Chlorine Floater In Pool While Swimming?


2. Using a skimmer:

swimming pool skimmer

A pool skimmer is part of the main filtration system whose work is to trap and suck up leaves, particles, and dirt floating in the swimming pool.

Most pools have this installed but if you don’t you can use one of the other methodologies in this section. Empty the skimmer off its debris and drop the tablets into it.

It is much easier to do without worrying about the tablet not dissolving evenly.


3. Automatic chlorinator:

Inline chlorinators aren’t always installed in most swimming pools but if you have one, all you need to do is to unscrew the opening of its canister, drop the tablets, close the canister and turn on the filter system.

The automatic chlorinator works in a way that water from the swimming pool passes it at equal speed and cycle of flow. It is very accurate in dissolving chlorine tablets.


4. Making them into granules:

This is only advisable to be done only if the aforementioned is not available. Crush the chlorine tablets into powdery form and sprinkle them on the pool surface. It is not advised but it will make noticeable differences rather than not doing anything at all.


When Can I Start To Swim After The Chlorine Tablet Application?

Chlorine tablets generally have a pH of 2.9 which is toxic to the body. After application, give the swimming pool up to 3 hours before any activity. Your product’s manufacturer will surely give instructions on when you can resume swimming, you can follow the instruction too.


How Long Does A Tablet Of Chlorine Last?

The activities and environmental influences determine this. For an averagely used home swimming pool, chlorine tablets are to be applied once a week but if after a test for free and total chlorine and you get below required, you can proceed to give another dosage of chlorine tablet.

Alternative to chlorine tablets

  • Granular chlorine (powdery chlorine)
  • Liquid chlorine


Liquid chlorine vs chlorine tablets

Liquid chlorines are mostly used in shocking the swimming pool while chlorine tablets are for regular maintenance purposes. In cases where chlorine tablets are the only source of chlorine, there are observed increase in chloramines. At the same time, pools dependent on liquid chlorine waste a lot of useable chlorine.

The two should work in hand and each condition should warrant their usage.


Final Thoughts

Your swimming pool might be in the regular league of those which take 2 – 4 tablets of chlorine tablets with the information provided, always put chemical content testing first before proceeding. Pool test kits will save you the stress of having to correct imbalances in everything or be exposed to unnecessary health issues.

Leave a Comment