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Water Care Advice

Can I Set Chemical Threshold Levels in My Pool?

Can I Set Chemical Threshold Levels?

Owning a pool offers many opportunities for relaxation and recreation. When the sun comes out in full force, you can take a dip and cool off. When birthdays or momentous occasions come around, you can throw a poolside party where everyone has a good time. 

But sparkling, clean water that beautifully reflects the sun's rays is more than a random miracle. That type of pool appearance demands a lot of effort and work to maintain. 

The chemicals you put into your pool are crucial to achieving that classic, crystal-clear look. The chemical levels in pools can seem like a balancing act for some pool owners. How much of which chemicals should you put in? 

In this article, we'll discuss the pool water chemical ranges that contribute to a clean, appealing pool. By knowing and setting the correct chemical threshold levels, you can achieve a pool your friends and family will be excited to jump into. 

Major Chemicals That Go Into a Pool

You'll need to put several main chemicals in your pool to keep it clean and safe. Here's a closer look at these chemicals. 


The chemical chlorine may be one of the most recognizable on this list. Many people closely associate pools with chlorine, but knowing what it does besides “keep the pool clean” may be a different matter. It's important to know what it does scientifically to achieve the best outcomes in your pool. 

Chlorine destroys algae and bacteria through its disinfecting properties. It also oxidizes, a word that means “chemically destroys,” various other particulates in the pool, including dirt and chloramines. 

Chloramines are an unwanted byproduct of chlorine's oxidation process. They have a signature unpleasant smell, but adding more chlorine to the pool at proper intervals will remove them. In other words, more chlorine gets rid of chloramines.  

This is a process known as “shocking,” or “superchlorination.” This is the act of raising the chlorine level of a pool to five to 10 times the normal level to oxidize the chloramines, leaving only free chlorine in the water to continue disinfecting and oxidizing. 

Chlorine exists in all three states of matter — solid, liquid and gas. Each state of chlorine contains differing chlorine levels, with gaseous chlorine being the most toxic. 

Cyanuric Acid

Chlorine is one of the most common ways of disinfecting a pool, but the sun's ultraviolet (UV) rays can put a stop to that. UV rays decompose free chlorine, weakening and stopping it from cleaning your pool as it should. This is where cyanuric acid comes into play. 

Cyanuric acid provides a stabilizing effect to chlorine, helping it resist deterioration from the sun's UV rays. When you add cyanuric acid to your pool — or use a stabilized chlorine product that contains cyanuric acid — you're preserving the chlorine's ability to continue oxidizing and disinfecting the pool water. But knowing how much cyanuric acid to use can be tricky. We'll get into that more in a later section. 

Cyanuric Acid


For people who want to avoid chlorine, bromine is one of the most popular alternatives. Bromine helps keep pools clean by ionizing contaminants that enter the water. The process of ionization involves breaking the bonds that hold molecules together. Forcing the molecules apart destroys them, leaving the pool water safer and cleaner. 

One reason some people choose bromine over chlorine is that it has a longer life in the water. This means it remains active longer, ionizing the water without breaking down. A longer life means you can avoid adding bromine to the water as often as you would have to add chlorine, barring other circumstances. 

The downside of bromine is that, like chlorine, it leaves behind waste products called bromamines as it decomposes. Bromamines are less unpleasant than chloramines, but they do reduce the effectiveness of fresh bromine. Shocking the pool will get rid of these bromamines, returning the effectiveness to fresh bromine. 


Biguanide is a lesser-known pool chemical, but it has its share of users because it is a chlorine-free sanitizer. It began as a surgical disinfectant and shares similarities with hydrogen peroxide. 

As opposed to bromine and chlorine, which ionize and oxidize pool water, biguanide forces contaminants to bind together. This results in clumps of water-insoluble materials in the pool water. The pool filter can then easily filter out these chunks because of their increased collective sizes. 

Here are some of the upsides of biguanide:

  • No chloramines or bromamines to deal with
  • Gentle on skin, eyes and hair
  • Resists degradation from the sun's UV rays

But biguanide also has some drawbacks you should know about:

  • More expensive and less effective than other pool sanitizers
  • Stops working over time
  • Can make pool water cloudy


Many types of minerals from the earth are healthy for humans in small doses. Some of these minerals are also essential for a sanitized pool. Here are a few of the most common pool minerals:

  • Calcium: Calcium affects the hardness of pool water. Hardness refers to the level of minerals suspended in the water. With proper calcium hardness, the water's chemistry behaves more predictably. We'll get into this a bit more below. 
  • Silver: Silver is a bactericide, meaning it is great at destroying bacteria in the pool's water. 
  • Magnesium chloride: Magnesium chloride has a few benefits, including soothing swimmers' skin and fighting algae in the water. 
  • Copper: Copper is a known algaecide, making the water an environment where the various types of algae can't grow and multiply. 

Other Pool Chemicals

A few other pool chemicals exist that you may need to achieve the results you want. Here are some of the most common:

  • Algaecide: Chlorine is the best algaecide you can use, but you have to get the chlorine to the right levels. This can take a while. In the meantime, use a commercial algaecide to keep the algae at bay. That way, when the chlorine returns to the right levels, it can easily destroy any algae present in the pool. 
  • Clarifier: If you wake up to a cloudy pool hours before hosting a pool party, you're going to need some clarifier. Pool clarifier quickly clears pool water to make it look more appealing. Keep in mind this is only a temporary fix. The cloudiness will return when the clarifier dissipates. 
  • Flocculant: Flocculant addresses the root cause of pool cloudiness by causing the clouding particles to clump into larger particles and sinking them to the bottom of the pool. You'll have to use a pool vacuum to suck up these larger particles to get rid of them. 
  • Metal sequestrant: Some metal is good for your pool water. Left untreated, the metal content of your pool can stain pool surfaces. Use metal sequestrant to stop metal particles from settling on surfaces, eliminating stains left behind. It's good to have some metal sequestrant if you fill your pool with well water or hard water. 

Why It's Important to Keep Chemicals in the Right Range

Why It's Important to Keep Chemicals in the Right Range

Keeping your pool chemicals in the right range is one of the most important things you can do as a pool owner. This task, also known as “water balancing," requires an understanding of the relationship between different pool chemicals and the parameters of these chemicals. 

Water changes year-round. Everything from dirt, sweat, oils and cosmetics influences the pool water's chemical balance. While properly balanced water can resist major swings in the changes of this balance, you'll have to add more chemicals to maintain or return them to their proper ranges. 

In ideal situations, you will keep the same water in your pool for many years. You can achieve this with proper filtration methods and an appropriate chemical balance within the water. When you think of a balanced pool, you must also think about three things — the water's pH level, alkalinity and calcium hardness. Below, we'll take a closer look at these three crucial ideas that go into balancing the water in your pool. 


pH is the measurement of how basic or acidic the water is. You can read your pool water's pH by using a scale that ranges from 0 to 14. On the pH scale, 7 is neutral. Anything below 7 is acidic, and anything above 7 is basic, or alkaline. 

The ideal pH of a pool is 7.4 to 7.6, which is slightly basic. Proper chemical levels in your pool let you achieve this ideal pH level. Keeping up with your pool chemicals is so important because everything that enters your pool has a pH of its own. These materials may be acidic, causing your pool's pH to dip below the ideal amount. They can be basic, causing your pool's pH to increase. 

An acidic pH level means your water is becoming corrosive and can begin eating away at pool surfaces. An overly basic pool pH leads to the depositing of minerals on pool surfaces, a phenomenon known as “scaling.” In both instances, adding the appropriate chemicals to raise or lower the pH level will bring the pool water back to its ideal state. 

Total Alkalinity

Alkalinity and pH work hand-in-hand when maintaining balanced pool water. Alkalinity is water's ability to resist pH changes. In other words, your pool water's stable pH levels depend on the water's total alkalinity. 

Bad alkalinity levels cause your pool's pH levels to change drastically. But adding acids or bases to your pool also affects its alkalinity. Adding bases raise the pool's pH levels and total alkalinity, or ability to resist pH changes. Lowering the pH of your pool by adding an acidic product also causes its alkalinity to decrease, making the water less stable. 

Calcium Hardness

Calcium hardness is the measure of the level of calcium carbonate particles in the pool's water at a given time. Hard water has a high level of calcium, along with other minerals including magnesium. Higher hardness levels lead to a saturation of the water. When water becomes saturated, it starts depositing minerals on surfaces. This results in scaling, as mentioned above. 

Soft water has the opposite effect. It absorbs calcium from surrounding materials, leading to the corrosion of pool surfaces. This is why you must strike a balance of calcium hardness in your pool's water. If the water is too hard, it will lead to unattractive scaling. If it's too soft, you'll experience damaging corrosion. 

What Are the Correct Levels for the Chemicals?

Now that you know more about pool chemicals and why it's so important to strike the right balance, it's time to learn about the correct levels for these chemicals. Meeting these levels will help you achieve pool water that is just waiting for people to jump into and enjoy. 

What Are the Correct Levels for the Chemicals?

Here are the appropriate levels for pool chemicals:

  • Chlorine: The Centers for Disease Control and Prevention (CDC) recommend using at least one part per million (ppm) of chlorine in swimming pools. You can safely go up to three ppm, but you should avoid going much higher than that for regular swimming levels. 
  • Cyanuric acid: Keep cyanuric acid at a level of 30 to 40 ppm.
  • Calcium hardness: The ideal range for calcium hardness in a swimming pool is 200 to 400 ppm
  • Bromine: Bromine is comparable to chlorine in that you want to achieve a level around two to three ppm in your swimming pool if you use it. 

Monitoring Chemical Levels

Once you balance your pool water, most of your efforts will go toward maintaining it at its correct levels. Here are some recommended testing and monitoring timeframes according to the Florida Administrative Code for swimming pools:

  • Chlorine: Record your results for chlorine levels daily. Keep indoor pools at five or lower chlorine ppm. 
  • Cyanuric acid: Check cyanuric acid levels one or two times weekly. 
  • Bromine: Like with chlorine, check and record bromine levels in your pool once per day. Keep indoor pools at six or fewer bromine ppm. 
  • Calcium Hardness: Test your pool for calcium hardness levels once every week. 
  • pH: Check your pool's pH levels daily. 
  • Alkalinity: You should check your pool's alkalinity levels once every week. 
  • Total dissolved solids (TDS): A high TDS will make your pool's water taste salty. Check TDS levels once every month. 

This can be a lot to keep straight. Thankfully, technology exists to make this process easier than ever. WaterGuru SENSE sits in your pool's skimmer and measures the water levels in real-time. It sends this information right to your smartphone via a pool chemical app so you always know what your pool's water needs to stay balanced. 

Monitor Your Pool's Chemical Threshold Levels With WaterGuru SENSE

Are you ready to experience a new, easier way to monitor your pool's chemical thresholds? If so, then WaterGuru SENSE is the piece of the puzzle you've been looking for. With its state-of-the-art technology and ease of use, you'll always know which chemicals you need to add to keep it ready for the next pool party or casual Saturday afternoon. 

Buy WaterGuru SENSE today and take the next step toward a cleaner, healthier pool.  

Monitor Your Pool's Chemical Threshold Levels With WaterGuru SENSE

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