Muriatic Acid Vs Hydrochloric Acid Vs Sulfuric Acid
There are three very common types of acid that can be used in water, which include muriatic acid, hydrochloric acid, and sulfuric acid. Both muriatic acid and hydrochloric acid are highly similar in composition. In general, muriatic acid is a less pure form of hydrochloric acid. In order to obtain its potency, contaminants are added directly to the muriatic acid. As for hydrochloric acid, its commonly used in laboratory applications. Since muriatic acid isnt as pure as hydrochloric acid, its also less expensive.
When looking specifically at sulfuric acid, this is a form of acid that can be used alongside muriatic acid to lower the pH levels of your pool water. However, muriatic acid is less expensive and doesnt come with the side effects that result from sulfuric acid. While its possible to use sulfuric acid to lower pH levels of pool water, this acid is stronger and more harmful than muriatic acid. When used in pool water, sulfuric acid creates fumes and can add total dissolved solids to the water, which increases the possibility of corrosion. Likely the best option for lowering the pH levels of your pool water is muriatic acid.
How To Lower Alkalinity In Your Pool
- |January 30, 2021
Total alkalinity keeps your pool waters pH level in check by absorbing fluctuations in the water balance. In other words, its a pH buffer.
The ideal range for alkalinity in your swimming pool is between 80 and 120 parts per million, and anything above that will ultimately lead to issues with your water chemistry.
Lets talk about why this happens, why it matters, and how to lower alkalinity in your pool the correct way.
How Much Acid Should I Add To My Pool
This depends on how high your pool’s pH is and the size of the pool. If you are using test strips, it’s usually hard to determine exactly how high the pH level is; you just know it’s high. A better test kit, or a DPD drop test kit, will use phenol red to give you a better idea of your true pH reading. Some better test kits include an “acid demand” test to help calculate a more precise dosage.
If you have a pH reading of 7.8 or higher, and an average size in-ground pool, you should add 1/4 gallon of muriatic acid, and re-test after the water has circulated for an hour. If you have a smaller pool, or an above-ground pool, you would start with one cup of acid, and then re-test and add more if needed. If you have a spa, we are talking only capfuls at a time. Very little acid is needed to adjust pH in a spa.
For a more exact idea of how much acid to add, see the table below or use a pool calculator, which can be found online, that will give you an amount based on estimated pool volume and chemistry.
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Why You Have High Alkalinity
When the pH goes up, it enters into alkaline territory on the pH scale. This rise will gradually increase the total alkalinity level as well. Theres a few reasons why this occurs.
When swimmers enter the pool, they bring with them their own pollutants that affect the water chemistry. These can be anything from natural body oils, to sunscreen or lotions they may have applied to their skin.
The water that is being used to refill the pool can also be a culprit. If its high-alkaline water to begin with, you can bet it will affect the pools total alkalinity.
Another cause for high alkalinity can be when you shock the pool. While this is performed to quickly rid the pool of pollutants, chlorine-based pool shock is highly alkaline, and can raise the waters total alkalinity level in the process.
What Is Ph In The Pool And Why Is It Important
pH is used to describe a scale of acidity or basicity of a solution. Ranging from 0-14, a pH of 7 is neutral, anything less than 7 represents an acidic or low pH solution, and anything more than 7 represents a basic or high pH .
The pH, as well as alkalinity, is probably the most important value to stay on top of in your pool. Its best to maintain a slightly neutral pH between 7.4-7.6 with an alkalinity level between 80-120 ppm. ;;;;;;;;;;;
Factors that cause pH to change in your pool:
- airborne debris
- swimmer wastes
When the pH shifts out of balance, it can wreak havoc on your pools chemistry and balance as it directly affects some of the chemical reactions that take place.
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Lowering Total Alkalinity Without Affecting Ph
Can the Acid Slug Lower Total Alkalinity Without Affecting pH?
The ability to control whether you lower Total Alkalinity or pH by the method in which a dose of acid is added to a swimming pool would certainly be of great value to the Pool Operators.
To lower Total Alkalinity drastically with only a slight effect on pH, simply take your dose of acid and pour it slowly into one spot in the deep end of the pool. Youll actually see the bubbles forming around where the slug is added that is, the bicarb burning off and bubbling up. If you wish to lower the pH without also reducing the Total Alkalinity, simply pour the dose of muriatic acid about the pool.
This would all be wonderful if it was only accurate. Still, just like the mythological Chlorine Lock, folkloric tales within the swimming pool industry do persist. But, Lowering Total Alkalinity Without Affecting pH?
When hydrochloric acid is added to water, the molecules disassociate into both hydrogen ions and chloride ions . This happens, no matter how it is added. To keep it simple, when you increase the number of hydrogen ions in a solution, the water becomes increasingly acidic. Remember, pH stands for Potenz Hydrogen, which can be interpreted from the original German to Hydrogen Concentration. So, if adding acid to water increases the hydrogen ion concentration no matter how you add it and pH is the Hydrogen Concentration Hmmm?
Low Ph Is An Easy Fix
Raising the pH level of a swimming pool is as easy as adding more alkaline materials. Soda ash and sodium bicarbonate are two common alkaline products that can be used to raise pH levels in a pool. Remember that optimal pH levels for a swimming pool are between 7.4 7.6! If you overshoot it and need to bring your levels back down, read my guide on how to lower your pool pH level.
Questions? Shoot us a note!
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When Is Ph Too High
pH is the level of acidity in your pools water.
This acidity needs to be balanced. Too much causes problems as the water becomes alkaline, and too little causes problems as the water becomes acidic.;
The pH scale measures from 0 to 14, and the ideal reading you want to keep you water at is between 7.4 and 7.6.;
Some pool owners use a wider range of 7.2 to 7.8 for a bit more leeway, but a pH level of 7.5 is what you should always be aiming for.;
Use Food Grade Hydrogen Peroxide To Lower Chlorine
Yes, the stuff sitting in your first aid kit. But a much, much stronger version of it.
First aid hydrogen peroxide is about 3% concentrated. Food grade hydrogen peroxide is about 35% concentrated.
A gallon of it shouldnt be more than 20 bucks, and you likely wont need more than half.
Similar to sodium thiosulfate, hydrogen peroxide also has the side effect of lowering pH. So make sure to test your water after each treatment.
To start, add a cup of peroxide to your pool to lower chlorine. Test your water a few hours later and readjust chemicals as needed.
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Summary Of Balancing Ph And Ta
– In any case, you get your TA levels lower than recommended levels that are between 80 and 120ppm but pH level is OK, use alkalinity increaser to raise TA back.;
– If you have low pH but the TA level is OK, use borax to raise your pH without raising your TA levels.;
– Use muriatic acid to lower both pH and TA when high. Use borax to help you raise pH when TA level is still high and you need to add muriatic acid so that you don’t get your pH lower than 7.0.
– Finally, it’s not possible to have low pH and high TA in the same water, or high pH and low TA in the same water. If you have one of the two situations, something must be wrong with your test kit and you need a better one.;
Achieve The Ideal Ph Balance With Muriatic Acid
When used correctly, muriatic acid can lower the pH levels of your pool water. The potency of muriatic acid makes it beneficial at getting rid of hardened water that has become too alkaline. Its also much more affordable when compared to sulfuric acid and hydrochloric acid, which is why its recommended that you use it for your pool cleaning needs.
While there are a wide range of pH sensors that will allow you to accurately test the chemistry of your water, likely the best option for testing pool water would be the pH1000 sensor, which is designed for light-duty use and has a fast response time.
If you need any help in understanding the proper composition of water or how to test pH levels, contact Sensorex today!
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Simple Science Goes A Long Way
Maintaining the proper balance of chemicals in your pool is a continuous process. Any new material that enters your pool , will influence the waters chemistry. In addition to pH, it is important to monitor total alkalinity, calcium hardness and total dissolved solids. Pool health is also your health, your time and your money. With the proper professional products and weekly testing, maintaining balanced water chemistry will become an efficient, simple process.
How To Lower Ph Levels
Before doing anything, always test your water first.;Use a pool test kit;to check the pH, acid demand, and total alkalinity.
Once youve determined that the pH level is too high, you should now work to restore the balance. There are two main products for lowering the pH. These are sodium bisulfate and muriatic acid.
Here are the steps for each product:
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How To Lower Ph In Pool Water
Lowering the pools pH can be done in a number of ways using a variety of pool water products. The first one we recommend is muriatic acid,; also known as hydrochloric acid, which is especially useful for larger pools.
Make sure to purchase one that is meant for swimming pools or spas to get the correct concentration level.
Read the instructions carefully, as some muriatic acids are pre-diluted and can be added to the pool directly.
Others may need mixing in a bucket of water before putting it into the pool.
Remember, always mix chemicals into the water, not the other way around, as you want to avoid the concentrated acid getting splashed up if the water is added.;
How much you need to add will depend on the size of your pool, as well as its current pH level.
As with all pool chemicals, be sure to wear protective clothing in case of spills.;
Another product you can use to decrease the pH of the water is sodium bisulfate, also known as dry acid. This acid has the advantage of being easier to handle than muriatic acid. Follow the instructions carefully as different manufacturers have different instructions.
With both of these products, make sure to add them in front of the return jets and wait 4 hours before anyone gets in to ensure that the acid has circulated evenly throughout the water.;
What Is The Ph In Your Pool
pH is the measure of hydrogen ions in a liquid, like the water in a swimming pool. pH is measured on a scale from zero to fourteen with one end representing an acidic solution and the other representing a basic solution.
A perfectly neutral solution, like pure water, falls in the middle of the scale at a pH of seven. Pool water is mixed with chemicals, primarily chlorine, to kill bacteria and maintain sanitary swimming conditions. Since pool water contains chemicals, it will not be a perfect neutral. An ideal target for optimal pool water is a pH of 7.4, which is slightly basic.
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Take Accurate Readings Of Ph And Ta In The Pool
I always use a LaMotte ColorQ Pro 7 digital test kit to do this. Let’s say that the pH reads 8.3 and total alkalinity reads 280 ppm, which are the real values from a pool I worked on last. Your readings may be higher or lower, but let’s just use these numbers as an example to help you understand this process.
How Much Sodium Bisulfate To Lower Pool Ph
Below you will find the approximate amounts of pH Decreaser you will need to lower the pH and alkalinity in your pool.
The amounts below are approximate. Its always best to read the manufacturers guidelines. Its also best to add less than you think to avoid overshooting your target pH level.
* Approx. amount of sodium bisulfate needed to lower pH level and alkalinity. Amounts are calculated based on 10,000 gal of pool water.
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Calcium Hypochlorite Chlorine Shock
The most common cause of high pH in a swimming pool or spa is the type of sanitizer or chlorine shock we use in the pool.
Calcium hypochlorite or granular chlorine is non-stabilized chlorine that comes with high pH levels, and if pH level is not monitored properly, you will have high pH issues in your pool and spa.
At The Summer Pools, we always recommend using;liquid chlorine, also known as sodium hypochlorite.
Sodium hypochlorite is pH neutral since it produces hydrochloric acid and sodium hydroxide as bi-products, and hydrochloric acid will naturalize the pH that is produced by sodium hydroxide.
If you have a saltwater pool, a saltwater chlorine generator will produce chlorine using sodium through a process called electrolysis, where the only bi-product is sodium hydroxide that has high pH levels above 13.
This explains why pH levels tend to get high in saltwater swimming pools and can only be offset by adding strong acids like muriatic or hydrochloric acid and sulfuric acid.
You Recently Shocked Your Pool
Shocking your swimming pool refers to the process of adding chemicals usually chlorine to stabilize the pH level.;
Shocking breaks up combined chlorine killing algae, bacteria, and other pathogens and it rapidly increases your chlorine level.
Combined chlorine is essentially chlorine thats bound to ammonia and nitrogen. Translation: its an ineffective sanitizer when in this state.;
Adding shock breaks up the combined chlorine and creates an increase in free chlorine. This increase can spike your pools pH level.;
Pool shock is available in both chlorinated or non-chlorinated versions. If your pool already has a high pH level, using chlorinated shock will only make things worse.
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Drain And Refill Pool
If youve ever found yourself in a situation where your pools Total Dissolved Solids were too high, then this might sound familiar.
Eventually, there comes a point when your pool water to be replaced. Sure chemicals keep it clean, but water can only be recycled for so long.
If youre only trying to reduce your waters chlorine by 1 ppm or so, then this might be one your fastest options.
This is a natural way to reduce chlorine, but it does come with some downsides.
Diluting your water lowers all of the other chemicals in respect. So be sure to do a full chemical test after to adjust chemicals as needed.
If youre pressed for time and dont mind dishing out a few bucks, a chlorine neutralizer can be the perfect quick fix for you. You can pick one up at your local pool supply store.
That said, be sure to research products and read reviews before buying. Some products work better than others.
We recommed Leslie Pools Chlor Neutralizer.
Depending on how high your chlorine is, you may need to use more than one treatment. So be sure to follow all included manufacturer instructions when lowering your pool chlorine with a neutralizer.
How Does Aeration Increase Ph Levels
When you aerate, you are exposing the water to more oxygen in order to do away with some of the carbon dioxide. When carbon dioxide mixes with water, it forms an acid we call carbonic acid, which lowers the pH levels. On the other hand, when acid is removed from the water, the pH level rises. Aeration literally removes carbonic acid from the water, which then raises the pH levels.
I always recommend natural aeration because with this method, you cannot over-aerate your pool, which is a very common issue when aeration equipment is used.
As a matter of fact, over-aeration is dangerous since you need some carbonate to act as a pH buffer. Carbonate is useful in plaster pools because it prevents the plaster from dissolving. In the case of over-aeration, pH will rise above the recommended levels while calcium carbonate will reduce below the required level. To fix this, you’ll need to adjust the pH and calcium carbonate levels to avoid any further damage.
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