It is super important to add chemicals to your swimming pool in a specific order.  This is not only for the most efficiency, but for the safety of the surface, equipment and monst importantly…YOU!  Before even considering adding a chemical to your pool, it is important to know what each chemical is and what it does.  This knowledge can be obtained from reading the product’s label, talking with a pool professional or if you really want to get advanced, the SDS sheets.  SDS sheets tell you everything one would need to know about a chemical.  The hazards, the combustion ability and even how to safely clean them up , in the event of a spill.  These are readily available online. is one place to get them.  The number one safety rule of water chemical safety is ALWAYS add the chemical to water.  NEVER add water to the chemical.  This could literally kill someone.  Wearing the proper PPE (personal protective equipment) is also advised and one of the things on the SDS sheets as well.  Never mix chemicals and always use a clean scoop.Never use the same scoop for different chemicals.  ALways know the gallonage of the pool so you know what amounts to add.

Whether doing regular water chemistry adjustments to your swimming pool or doing a new pool start up, there is a safe and specific order to add the necessary chemicals.  If you are uncomfortable or unsure, many pool companies can offer advice in their stores or even offer the service of coming out to your home.  If you aren’t sure–don’t.

There are nine steps.  The first 3 are “balancing” for the water.  The rest are turning your tap water into pool water.

#1 Chelating or Sequestering Agent

Chelating agents  are defined as: “Chelating agents are organic compounds capable of linking together metal ions to form complex ring-like structures called chelates.” ( A sequestering agent is defined by: “Sequestering agents are used to link undesirable metal ions together to form a stable structure that does not readily decompose”. (

Basically they clump everything together to keep the ions from dropping out suspension.  These would be any metal removal product or stain and scale removal.  These are important in preventing a bad chemical reaction when chlorine and copper combine and also helps aid in staining and scaling.  Pro Tip: Take your water into a pool store periodically and have them test for metals.  You can also purchase your own metal test strips and check at home.

#2 Alkalinity Adjusters

Alkalinity works as a “buddy system” with your PH.  They travel up and down together most of the time.   The alkalinity acts as a buffer to help keep the PH stable.  Think of it as the safety on a football team.  Sometimes, the alkalinity gets too low or too high. If the alkalinity is too high you will need to lower it with either dry or muriatic acid. The only way to lower JUST the alkalinity is with Co2.  Otherwise you will be lowering both the alkalinity and the PH.  If your alkalinity is too low, you will need alkalinity up (sodium bicarbonate).  An ideal range for alkalinity is 80-100. Pro tip:  If your CYA level is over 60 ppm, deduct 30 ppm from your alkalinity reading.

#3 PH Adjusters

Now that we have our alkalinity balanced, we can get an accurate PH reading.  A common mistake people make, especially salt pool owners, is to only check the PH and not the alkalinity. They read a “high” PH and keep adding acid. When the alkalinity is low, it causes the PH to be unstable and to  “bounce around”.  

If the PH is high, we need dry or liquid acid to lower it.  If it is too low, we need PH up, which is also known as Soda Ash.  Similar to baking soda, but not QUITE.  This goes directly into the pool.  Pool Pro Tip:   Did you know our body’s PH is a 7.4?  This is not only the most comfortable range for swimmers, but allows the chlorine to be most effective.

#4 Calcium Hardness Increasers

A lot of places have “hard” water right from the tap.  This means it contains higher levels of calcium from the get-go.  But in a lot of regions, especially those regions with heavier rainfall, the water comes out with lower amounts of calcium.  The recommended level for calcium is between  200-400 ppmIf your water is lower than 200 ppm then you will need to add a calcium elevator (calcium hypochlorite).  Since the water cannot naturally pick up calcium from stone and rock like it does in the wild, it will seek out calcium from the surface of your pool.  This is no bueno!  The only way to lower calcium is to drain some water, but check your source water first because if it is already high, this will be a moot effort. Pro Tip:  Never add a PH/ALkalinity adjuster the same day as calcium elevator.

#5 Chlorine Compounds

Now it is time to add our sanitizer.  Most outdoor swimming pools use chlorine.  Chlorine comes in granular, liquid and tablet form.  Please note that tabs are not designed to raise chlorine, but to maintain a chlorine level of 1 ppm or higher.  You will first need to establish a chlorine reserve.  This is done by adding chlorine.  Chlorine comes in Calcium Hypochlorite, Trichlor, and DiChlor and are each with their own pluses and minuses.  Speak with a pool professional about which chlorine is right for your pool.  Pool Pro Tip:  Did you know “shock” is actually not a product, but a method?  To shock a pool in layman’s terms means lots of chlorine and lots of oxidation.  Products are labeled “shock” to help the consumer know this is what you would use to accomplish shocking.

#6 Water Clarifiers

Sometimes there are particles in your swimming pool that are just too darn small for your filter to filter out.  In these cases, such as after an algae treatment, we need the help of a clarifier.  There are 2 main categories of clarifiers.  One version clumps the particles into larger pieces that can be vacuumed up.  The second version literally eats away at the particles.  Both will leave your pool as sparkly as ever!  Pool Pro Tip:  Never add a sequestering agent the same day as a clarifier.

#7 Algaecides

Now is the time to add any preventative algaecide you may want.  Algaecides do not guarantee against algae blooms, but can make then less severe.  Kind of like a flu shot.  Make sure to learn about the different types of algaecides and how they go about killing the algae to determine which will be best for the kind of algae your specific pool is prone too.  A lot of algaecides have both a treatment dose and a maintenance dose.  Pro Tip:  A lot of algaecides utilize the chlorine in the water so make sure to always add extra.

#8 Cyanuric Acid (AKA Conditioner, Stabilizer)

Cyanuric acid (CYA) is like a sunscreen for your chlorine.  It prevents it from burning off in the sun within a matter of hours.  It comes in liquid or granular.  Both go into the skimmer. Regular pools need a minimum of 30 ppm- 50 ppm.  We don’t want to have TOO much because it interferes with the efficiency of the chlorine.  Anything over 99 is way too high.  The only sure way to lower CYA is draining the water down, although studies are being conducted with certain products that may change this.  Pool Pro Tip:  If you float tablets, when the water gets below 70 degrees, take the tablets out.  This will help with the CYA building up too quickly and causing a need to drain prematurely.

#9 Phosphate Removers

These are typically added to the skimmer.  There are products to keep low phosphates low and products that are used as a treatment for higher levels of phosphates.  Phosphates are anything organic: leaves, pollen, dust, even the source water.  Phosphates are food for algae.  You don’t want a Las Vegas buffet laid out for your algae if you were to get a bloom.  Pool Pro Tip:  Net the leaves out of the pool as soon as possible to help keep phosphate levels low.

Always practice safety when adding chemicals to your pool.  Follow the directions.  Always have the pump running when you add chems and let it run for a period after, depending on the product.  See you poolside!