Tuesday, May 21, 2024
HomeExclusiveHow To Lower Ph In Pool Water

How To Lower Ph In Pool Water

- Advertisment -

Ph And Chlorine Strength

How To Lower Swimming Pool pH Level Using Muriatic Acid – Tutorial

Ah yes, chlorine strength. This is the main reason health codes demand a pH maximum . See the chart on the left below.

Without cyanuric acid in the water, the pH determines the strength of chlorine, as expressed by the percentage of the strong, killing form of chlorine, Hypochlorous Acid . %HOCl is usually what we use to determine chlorine strength. Well, that and ORP.

The lower the pH, the higher the %HOCl, the stronger and faster the chlorine. Most indoor pools do not have CYA in them, so that chart absolutely applies to natatoriums. Outdoor pools with CYA, however, can have virtually the same strength of chlorine at 8.2 as at 7.2. See the chart above on the right side, with just 30 ppm CYA. The %HOCl is way a the bottom, and a negligible reduction occurs as the pH climbs. The FC:CYA ratio is what truly determines chlorine’s strength and speed in those poolsnot pH.

Baking Soda To Raise Ph And Alkalinity In Pools

Most people know that chlorine is an important chemical in keeping pool water safe for swimming. But adding too much chlorine can lower your pools pH as well as its total alkalinity. When alkalinity falls, it is more difficult to maintain a stable pH. Plus, a lower pH and alkalinity of your pool water creates several negative effects, from itchy skin and stinging eyes for swimmers to corrosion of your pool ladders, liner, or other components.

When your waters alkalinity is too low, any chemicals you add will exponentially affect the pH, creating a condition known as pH bounce. Youll also need to add more chlorine to get the same sanitizing effect, and your swimmers will complain. Overall, pool water with inadequate alkalinity levels can be frustrating and costly.

Fortunately, there is a simple and cost-effective way to maintain your pools alkalinity and pH. You might use it in your cookie recipes or to freshen your fridge. This handy tool for pools is none other than Arm & Hammer baking soda, although youll need pounds of it rather than a pinch.

What Does Baking Soda Do For A Pool

Baking soda, also known as sodium bicarbonate is naturally alkaline, with a pH of 8. When you add baking soda to your pool water, you will raise both the pH and the alkalinity, improving stability and clarity. Many commercial pool products for raising alkalinity utilize baking soda as their main active ingredient. You can maintain your pool for a fraction of the cost by going straight to the source and using pure baking soda in your pool.

You May Like: How To Build Your Own Inground Swimming Pool

You Have A Saltwater Pool

Saltwater pools arent immune to high pH levels. In fact, they can be more susceptible due to their chemical makeup.

Sodium in saltwater pools combines with hydrogen and oxygen molecules, creating a high pH byproduct called sodium hydroxide. If your pool isnt being regularly maintained, it can easily cause the pools pH level to skyrocket.

How To Raise Pool Ph Level

Relationship Between pH and Total Alkalinity

Sometimes the pH level goes lower than needed. If you were learning how to lower the pH level of your pool and it accidentally went too low, its time to bring it back into balance.

As for what causes low pH in a pool, that varies:

  • Leaves and pine needles may give you a lower pH reading. This includes the leaves on the pool cover.
  • A heavy rainfall, especially in a city, can lower the pH. Rain is slightly acidic and will lower the alkalinity.
  • Many people lounged in the water. Body oils and sweat may mean a low pH for your pool.
  • You used dry or muriatic acid to lower pH. It may have been too much or there couldve been other factors at play. Sometimes its a challenge to get the pH just right.

Although a low pool pH is uncommon, you can still balance it out. The pool water is too acidic now. That means you balance it with alkaline substances. Raise pool pH with borax, soda ash or aerate the water. Washing soda and sodium carbonate are other names for soda ash.

To use soda ash to raise pool pH, follow these steps:

  • Follow the directions on the package to learn how much washing soda to use.
  • Run the pool pump and filter.
  • Sprinkle the washing soda evenly across the whole pool.
  • Wait an hour for the soda ash to distribute throughout the water.
  • Test the water and proceed accordingly.

Follow these steps to raise pool pH with boric acid:

Ready to jump into pool maintenance? Get online orders of pool vacuums, brushes and other supplies delivered right to your door.

Shop this Project

Recommended Reading: What Size Pump For Pool

Keep Your Pool And Equipment Clean

Swimming pool water needs regular treatment to stay clean. An improperly treated pool will cause the pH balance to fluctuate, and a host of issues to take root.

This can be anything from mineral build-up, to cloudy water and algae blooms. Not only will the water be affected , but so will the pools filters and pump system.

Ph Down To The Rescue

If the pool pH is too high, or above 7.6, you need to lower it as soon as possible. To do this, you will need a pH reducing chemical. Our most trusted option is pH Down. It is the perfect and most efficient way to lower your pH to a desirable level again. The amount required is based on the number of gallons of water in the pool and the amount of alkalinity in the water.

You must keep your pool water chemically balanced. It is very important to remember that your pools health is also your health, your time, and your money. This is why iopool is here to help you will all your pool questions and needs.

Dora Griff

Recommended Reading: Clogged Skimmer Line

What Happens In A Low Ph Swimming Pool

On the other hand, swimming pool water with low pH levels is acidic this you can actually feel the difference as you take a dip and swim. If you swim in an acidic pool, expect skin irritation and burning eyes the moment you open them underwater.

Just like in an alkaline pool, chlorine and other chemicals may not be effective in pool water with low pH. Metal parts of your pool can also corrode, and vinyl linings may wrinkle if the water is too acidic.

Treat The Pool To Lower Ph Level

How to Lower Pool pH | DIY Pool Care | The Home Depot

Remember, always wear protective clothing when using pool balancers to re-balance the water. This includes goggles or safety glasses and rubber gloves.

When youve determined that your pool pH is too high, there are two ways you can balance it: dry acid or muriatic acid.

If youre using a dry acid, use these steps:

  • Follow the manufacturers instructions on the package. Use the recommended amount only.
  • Read carefully to see if you need to pre-dissolve the product to avoid surface discoloration.
  • You may be able to just add the dry acid. Do whatever the label says.
  • Make sure the pool pump and filter are running.
  • Spread the product in the deepest part of your pool.
  • Use a pool brush to break up any clumps. This will also help disperse the dry acid evenly.

If using youre using pool balancers with muriatic acid, use these steps:

  • Read the package and follow the manufacturers instructions.
  • In some cases, you may need to mix and dilute the product. If not, add the balancer directly to the pool as directed.
  • Slowly pour the product into your pool. Take care to avoid spills and splashes.
  • Run the pool filter and pump unless the instructions say otherwise.
  • Apply the pH balancing chemicals as detailed on the label.

Recommended Reading: Aria Versus Vdara

How Do I Know If My Ph Level Is Too High

The pH level of your pool should always stay between 7.2 and 7.6. Ideally, 7.4 is where you would want the level to stay, but it is tough to keep pH that stable. Most times, when you check pH, it will be somewhere within this range, and that is completely fine. When you start seeing numbers of 7.7 or higher, action needs to be taken to lower it.

Your Total Alkalinity Is High

Total alkalinity refers to the neutralization of acids and bases in the water. This is important as it works to stabilize the pH level, which in turn, affects the functionality of your pool.

The ideal range of alkalinity is between 80 to 120 ppm .

High total alkalinity is a common issue and there are steps you can take to reduce its level.

If left unchecked, it causes a chain reaction of events that will spike the pools pH level, leading to potential pool damage and skin irritation issues for those who swim in it.

When your waters alkalinity is too high, it needs to be lowered. This is usually done by adding muriatic acid.

Also Check: Mandalay Bay Beach Gazebo

You Have An Algae Problem

While your pool has a myriad of chemicals and sanitizers, algae can still bloom and cause your pH level to rise.

Algae is naturally occuring and is always in the water. Blooms are the result of inconsistent chlorine levels, unbalanced pH/alkalinity levels, poor water circulation, and poor filtration.

In addition to being an eyesore , algae can damage your pool. Thankfully, there are products like algaecide which are highly effective in getting your algae problem under control quickly.

Ph Control Vs Containment


Given the technology available for commercial and residential swimming pools, one could be justified for thinking pH can be controlled. But that’s wishful thinking.

Sure, with enough acid and other adjustment chemicals, you can force water’s pH to stay within a certain range , but doing so fights against physics. pH is a reactionary chemistry it moves around rapidly when you manipulate the water with chemicals, aeration, or just about anything else. It constantly fluctuatesmuch to the frustration of pool operators worldwide. This frustration is understandable, but it’s based on a fundamental misunderstanding that pH can somehow be controlled.

In reality, pH is supposed to rise, thanks to Henry’s Law of physics. It takes consistent use of acid or CO2 injection to suppress pH and keep it within ranges well below its natural ceiling. More on this later.

And yet, for indoor swimming pools , pH must be kept within certain ranges for optimal chlorine strength, which we will discuss next.

How to “control” pH

pH control is usually accomplished with a chemical controller that has a pH probe, and the ability to feed acid or CO2 injection as needed. We call these sense and dispense systems. They work kind of like a pH thermostat the probe reads a pH over a set point, and it feeds acid or CO2 until the pH gets down to the desired set point. The challenge with this, of course, is overcorrection, especially when your acid dose is not based on the current alkalinity of the water.

Don’t Miss: Target Pool Supplies

How To Lower Ph In Your Pool

  • |October 29, 2020

Owning a swimming pool comes with plenty of perks, but it also requires a maintenance schedule that can be frustrating if not followed regularly.

Youll have to learn how to lower pH in your pool, in order to maintain the waters proper pH level at all times.

If it becomes unbalanced , it can create a host of problems for your pool and anyone who enters it.

Skip to:

Test Your Water Regularly

Testing your water should be done at least once a week. This is because the pH level is extremely delicate and a drop or spike can easily occur when someone goes in the pool, when it rains, even when the outside temperature changes!

There are 3 types of kits you can use to test for pH test strips, liquid kits, and digital kits. All are easy to use and will return easy to read levels when testing water samples.

Read Also: Pristine Blue Starter Kit

Sanitizers And Their Ph Impact

Every type of sanitizer has a pH impact on the pool, and the pH depends on the sanitizer used. For example, chlorine gas and trichlor are very acidic products, meaning they have a very low pH and tend to bring the pH of the pool down. Dichlor has a relatively neutral pH, as does bromine, so their pH impact is minimal, if not negligible. Non-stabilized chlorines like calcium hypochlorite , sodium hypochlorite , and salt chlorine generators all tend to raise the pH of the pool.

One common habit in the pool business is to add some acid to “offset” the pH rise that liquid chlorine causes. But according to renown pool chemistry expert Robert Lowry in his book Pool Chemistry for Service Pros , when liquid chlorine goes into the water, it actually won’t raise the pH as much as you might think. Liquid chlorine’s reactions create byproducts of both high pH and low pH , which neutralize each other. The net pH change should be about zero.

Sanitizer is only used in a few parts-per-million, so even if there is a net pH change, it isn’t always a big deal. With one exception. There is one sanitizer type that consistently raises the pH of a swimming pool: salt-generated chlorine.

2NaCl + 2H2O Cl2 + H2 + 2NaOH

salt + water yields chlorine gas + hydrogen gas + sodium hydroxide

In our experience, salt pools almost always have a pH that drifts up. The good news is, the pH rise is predictable and can be counteracted with a measured amount of acid or carbon dioxide feed.

Effect On Calcium Hardness And Tds


Neither the dilution of the pool nor the acidity of the rain will really affect the calcium hardness or total dissolved solids in your pool. However, rain will wash minerals and dirt off your pool deck and into the water, which may increase the calcium and TDS in your pool. This runoff can also affect your pools pH and TA.

To make sure that your pool remains safe to swim in, you need to rebalance your pool chemical levels before taking a dip after a rain.

Read Also: Does Target Sell Pools

What Does Rain Do To Pool Water

A pool is more than just water, so it makes sense that rain would affect it in some way or other. If its just rained and youre considering going for a swim, you may wonder if its a good idea.

The truth is that unless its been a very light rain, you shouldnt go swimming immediately after its rained the effect rain has on pool water makes it unsuitable to swim in directly after a storm. Here is what rain does to pool water:

Ph And Bather Comfort

Why are we told to maintain 7.2 to 7.8 pH in swimming pools, and ideally 7.4 to 7.6? Well, according to the textbooks and online resources, the industry standards from NSPF , APSP and other acronym organizations, two reasons are cited. First, pH controls the strength of chlorine, which we will discuss later in this article. The second reason is bather comfort.

Let’s just go right ahead and debunk this.

First of all, swimming pool water can irritate people’s eyes and skin…but we are not at all convinced it is because of the pH. We do not doubt that if pH is way low or way high that it will irritate bathers, because that should be obvious. The question is whether or not bather comfort is even noticeable within the pH parameters often seen in swimming pools. Let’s expand the extremes from 7.2-7.8 out to 6.2-8.8 pH, for ‘worst case scenario’ discussion. Hopefully your pool will not hit either of these extremes, but with overcorrections and etching plaster, these numbers are definitely possible in swimming pools.

Maybe. But we doubt it.

We have years upon years of competitive swimming experience to back up this opinion. We believe the primary cause of bather discomfort is disinfection byproducts like chloramines and other compounds. In other words, combined chlorine, non-living organics and other contaminants.

Read Also: Pristine Blue Pool Supplies

Reducers To The Rescue

To bring down pH, use a made-for-pools chemical additive called pH reducer . The main active ingredients in pH reducers are either muriatic acid or sodium bisulfate . Reducers are readily available at pool supply stores, home improvement centers and online.

Muriatic acid is powerful its used to etch concrete and you need to be careful when adding the chemical to your pool. It comes in liquid form, so you need to protect yourself from accidental spills and splashes. Always read and follow the manufacturers directions for safe handling, applying and storing of muriatic acid. A 1-gallon bottle is about $45.

Sodium bisulfate comes as dry granules and is considered easier to add and safer to handle than muriatic acid. Nevertheless, it should be handled carefully. Protect eyes and skin, and wear a dust mask to avoid inhaling any dust from the granules. A 25-pound bucket costs about $50.

The correct amount of a pH reducer depends on the water volume of your pool and its current pH level. Reducers usually come with a guide that takes into account the variables and calculates the proper amounts of pH reducer to add to your pool.

Why Pool Ph Matters

4 Ways to Lower Swimming Pool pH

Keep the pH of your pool at the optimum range to make sure that chlorine works most effectively. Youll enjoy every swim when your pool water is properly balanced. Knowing how to lower pH in water is a necessary DIY skill for pool owners. Its good to learn how to raise the pH as well.

When your pool pH is too alkaline, meaning the pH is too high, you may see these clues:

  • Calcium buildup
  • Skin gets dry and itchy
  • Cloudy water

Its not pleasant to swim in a pool with a high pH. However, the signs of a high pool pH arent too different from those when its low. Its always best to test the pool water before adding chemicals. Dont guess the pH.

Safety Tip: If your pools pH is sky high, regular ways of lowering it may not work. If you need to use strong additives like hydrochloric or sulfuric acid to balance it out, call a professional.

Read Also: How Much Chlorine To Shock A Pool Calculator

- Advertisment -

Most Popular

- Advertisment -