Barack has expertise in pool chemistry and pool maintenance. He writes in-depth articles about how to maintain pools for optimal enjoyment.
What Causes Rise in pH and Total Alkalinity in a Swimming Pool?
One of the major reasons why pH rises above the recommended level for a swimming pool is high alkalinity.
To avoid high alkalinity, add Alkalinity Increaser slowly by slowly while measuring its level and always ensure that your Total Alkalinity(TA) is within the recommended range of 80 - 120ppm because if it goes above 120ppm, your pH will definitely rise high.
The second cause of high pH in a pool is using Calcium Hypochlorite(powder chlorine) pool shock to sanitize pool water. Calcium hypochlorite comes with high pH and calcium level and will significantly increase pH in the pool if you don't take prior measures to balance your pH.
Also, an abnormal rise in TA might be caused by the water source. It could be possible that your pool fillwater is already high in alkalinity and will therefore increase your TA once it mixes with more Alkalinity Increaser you are using. Test your water source for alkalinity and use a different source if it has high TA because you'll need to use too much dry acid more often to lower both pH and TA in your swimming pool.
Getting a perfect balance of pH and alkalinity is a little tricky since acid will lower both but not at the same rate. If you have high pH and TA in your pool, here is the easiest way to lower and balance pH and TA in your pool without using any extra equipment like an aerator.
To avoid pH and TA issues, closely watch your alkalinity levels. You also have to be very careful when sanitizing your pool using granular chlorine to avoid pH and Calcium scaling. I highly recommend that you shock your pool using liquid chlorine.
This article is for anyone who needs to lower high total alkalinity (TA) and high pH down to the recommended levels for a swimming pool. All you have to do is add muriatic acid to lower both total alkalinity and pH, then aerate the pool to balance pH out.
It usually takes me an average of 48 hours to get the perfect balance of total alkalinity and pH. However, this process needs patience as it may take a day, two days, one week, or even longer, depending on how extreme the TA and pH levels are high in your pool.
How to Lower Alkalinity and pH
Natural aeration (not using any equipment to speed up the process) is highly recommended, but if you need faster results, I have included a list of equipment that will help speed up the process and instructions for how to use it at the end of this article. Extra care must be taken to avoid over-aeration if you decide to use aerators because over-aeration raises the pH levels and lowers the calcium carbonate levels beyond recommended levels, which can cause significant damage to the pool. Here is the process:
- Take accurate readings of TA and pH using a reliable test kit.
- Dilute muriatic acid and distribute it evenly in the pool. Use a pool calculator to get the exact amount of acid needed. Your target TA level should be 100 ppm.
- Allow the pool water to aerate naturally without using any aerators such as spa jets, waterfalls, fountains, return pointers, air compressors, or the like. Aeration helps bring up the pH level if it goes too low. The recommended level for pH is around 7.4 or 7.6.
- Take readings after six hours, then after 24, and then after 48 to make sure all chemicals are balanced. If you're lucky, and the pH level doesn't go below the normal range, then you do not need to do anything more.
- If pH levels are still too low after 48 hours, and you want to speed up the process, use an air compressor to accelerate the aeration process (optional).
What You'll Need
- Muriatic acid: The success of lowering alkalinity largely depends on the acid you use. I like using Sunnyside Muriatic Acid because it works very quickly. Some people use sodium bisulfate, but I find muriatic to be the most effective. Wear goggles, gloves, and long sleeves when working with this substance or any other chemicals.
- Accurate pool water test kit: I prefer the LaMotte ColorQ Pro 11 digital water test kit. You need a very accurate test kit for this process. The more accurate your readings are, the easier your work will be. Most of the test strips out there are not accurate and will make your job more difficult.
- Aeration: This is not a tool or chemical but a process that restores pH levels. (Don’t get tense. It's not rocket science!). pH levels may go down after a strong acid like muriatic is added, so aeration is needed to restore the recommended pH levels naturally without adding a pH increaser, which increases alkalinity.
Ideal TA and pH Levels
• Your target TA should be 100 ppm. TA in the 80-120 ppm is considered balanced.
• Your target pH level is around 7.4 or 7.6
1. 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.
2. Set a Target Value for Total Alkalinity
In the same example above, I set my target value of TA at 100 ppm. It is important to note that both the levels of TA and pH reduce when acid is added. A target value of 80 ppm or 90 ppm should be just fine, but I anticipated that the levels of pH would drop way below 7.0 when I add a strong acid, so my experience told me that 100 ppm was ideal for raising the level of pH later on through aeration.
Read More From Dengarden
Use a pool calculator to calculate the exact amount of muriatic acid you will need in order to achieve the target value of 100 ppm for TA, or whichever target value you have chosen.
In this step, don't worry too much about the pH yet. The main aim is to lower the total alkalinity to recommended levels. Later on, you can aerate to raise the pH level if it goes much lower than is recommended.
3. Dilute Muriatic Acid as Directed and Add It to the Water
The pool in my example holds 20,000 gallons. To get my target value of 100 ppm, I needed to add about 2 quarts of muriatic acid.
I usually distribute the muriatic acid solution slowly around the pool while the pump is running high to increase the effect.
Some pool managers prefer adding the muriatic acid solution in one spot. Personally, I don't like to do this because acid can damage pool parts when it is concentrated in one region.
The natural process of aeration begins after you add the muriatic acid and the levels of pH and TA have fallen and settled. During the aeration process, the levels of pH alone will rise gradually until it reaches the recommended level.
4. Test the Pool Water's Alkalinity and pH After 6 Hours
You will be watching for the changes in pH and alkalinity levels by doing a test after every 6 hours until it reaches the right range. If pH is within the normal range after adding muriatic acid, then you are done.
Taking the reading after six hours is just to help you know whether you are making any improvements in lowering the TA and pH. Amazingly, when I tested the water six hours later, total alkalinity read around 205 ppm (down from the original 280 ppm) and pH was at 7.6 (from where we started at 8.3). Your numbers may be different, but you should see a similar reduction in your process too.
5. Take Readings Again After 24 Hours
The next day, a full 24 hours since I started my test, the total alkalinity had gone down to 120 ppm. This is not the 100 ppm target value I set, but I was still impressed since 120 ppm is already within the recommended value for a standard swimming pool.
On the other hand, pH was lower, reading 7.1. I didn't worry too much about this because according to my digital pool water test kit and pool calculator, the lowest it pH can go is 6.8 and still be okay and non-destructive. Plus, the aeration process wasn't finished.
Since both chemicals were within a reasonable range, all was fine for me. So I waited to take my next reading in the evening, approximately 5 to 6 hours later. At that time, TA was ranging at 106 ppm, and pH had dropped to 6.9.
This means that total alkalinity was inching closer to my target value of 100, despite pH going down. (Again, don't worry much about the pH yet, because the "magical" aeration process is still going on.)
6. Take Final Water Test 48 Hours Later
After two days and two nights of keeping a close watch over the process, I took the reading in the morning. Total alkalinity in my example read 101 ppm, which is not bad at all. The pH was stable at 7.4. Remember that even if the natural aeration process is not complete, pH levels will not likely rise above the recommended levels because the alkalinity is within range and no pH increaser was used in this process.
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.
Overview of Aeration: Balancing Total Alkalinity and pH
Aeration is a complicated process. It involves pointing the returns upwards and running the pump on high speed to create surface disturbance, which introduces air. You must go through this process until the perfect natural equilibrium is reached between water and air.
How the Aeration Process Works
- You start by adding muriatic acid as needed in the pool. This will lower both the pH and total alkalinity. You must repeat this step until you get a perfect chemical balance.
- In most cases, when total alkalinity goes up, pH will drift up as well. Unfortunately, there is no pool chemical that can lower pH only without lowering total alkalinity—maybe one day chemical engineers will invent that kind of chemical :) In other words, if you lower a pH of 8.3 to the recommended level using muriatic acid, the total alkalinity will also reduce but will still remain on the higher side. Likewise, if you lower alkalinity to the recommended level (e.g., from 300 ppm to 80 ppm), the pH level drops way below the recommended level.
- If you add a strong acid like muriatic and then add a base like soda ash to raise total alkalinity, it will not work. This is because both chemicals (base and acid) will cancel each other, leaving your pool in the same initial mess.
- Aeration is a repetitive process that is done slowly, step by step. Your goal is to use muriatic acid to reach the target value of total alkalinity without letting pH go below 6.8. If the pH falls, you can raise it without affecting total alkalinity by aerating.
Accelerating the Aeration Process Using an Air Compressor
Using an air compressor at the surface of the water will add more disturbance and speed up the process.
- Try an air compressor with an end tube that has several tiny holes in it.
- Place it in the deep end. The small bubbles that escape from the holes produce carbon dioxide, which is released to accelerate the aeration process.
- Do this with the pump running high.
With an air compressor, it may take only a few hours to get TA and pH back to recommended levels.
Other Recommended Ways to Accelerate Aeration Process
- Use a degasser to remove carbon dioxide faster.
- Use venture injectors.
- Use manifolds with holes.
- Use a pressure washer aimed into the water to create turbulence.
- Use return lines that are aimed up (e.g., waterfalls or spillways).
Other Common Problems With Total Alkalinity and pH Levels
- If your pool has a high level of pH but total alkalinity is OK, pick up pH Reducer and get it down to recommended levels (between 7.2 and 7.8). And remember not to use muriatic acid in this case, since it will lower your TA. I always use liquid pH Minus by Kem-Tek, which is always very effective and quick compared to other brands.
- If you already know you have low pool alkalinity but pH is OK, get some alkalinity increaser to bring it back up to the recommended levels, and do it fast to avoid corrosion. Alkalinity Increaser by Pool Mate is one of my best options, since it is effective and pocket friendly. I have used it ever since I started in the pool service business, and I have never changed to any other. TA should be kept between 80 and 120 ppm for pools with liners and between 100 and 125 ppm for pools made of plaster.
- If your pH is high and alkalinity is low in the same water, you may need to add pH reducer/minus and then alkalinity increaser to your pool to lower pH and increase alkalinity respectively.
- In very rare cases, your total alkalinity may be high but with a low pH in the same pool. If so, using muriatic acid directly to lower TA is not a good idea since this will further lower pH down to very dangerous levels for a swimming pool. In this case, the best thing to do first is to use 20 Mule Team Borax to raise the level of pH without raising your TA, and then carefully add muriatic acid to lower both. This product is the most effective one I've found, and I use it for my clients. It is a better option than pH increaser/plus since it does not affect other chemicals in the pool but only increases pH.
Alternatively, you can naturally aerate (use an aerator if natural aeration is taking longer) your pool while the pump is on 24/7 to raise the level of pH up between 7.6 and 7.8 or higher, which might take a couple of days, and then lower both the TA and pH using muriatic acid slowly and carefully while watching on the pH levels not to go very down: Repeat the process until you get the required levels for both total alkalinity and pH.
Pool Alkalinity FAQ
Should I Use Soda Ash and Baking Soda to Raise pH?
Last month, a close friend of mine who has a plaster pool informed me that he had a huge drift in pH. I came to realize that he was using soda ash to increase the pH whenever it dropped below the recommended level, and baking soda to raise TA. Some parts of the internet recommend this as a quick fix, but don't do it!
Soda ash and baking soda raises alkalinity to abnormal levels, which in turn also increases the pH to a disproportionate amount. When I checked my friend's pool, pH was at 8.2 and was scaling up higher day by day. Total alkalinity was reading well over 280 ppm when the recommended values should be between 80 ppm and 120 ppm. Luckily, the calcium level did not scale as expected due to the calcium saturation index — it was within the expected range of 250 ppm. Calcium scaling causes cloudy pool water.
How Does High Alkalinity Harm Your Pool?
- A high TA level has the potential indirect risk of affecting how all chemicals function in a pool. For instance, the pH—one of the most important chemicals in the pool—is hugely affected by total alkalinity. When alkalinity goes too high, the pH will drift to the higher end and this will render all chemicals useless, including chlorine.
- On the other hand, when the TA goes too low, the pH will drift down. This is very destructive to the pool's structure and equipments, as well as harmful to human health.
- High total alkalinity is also associated with calcium saturation index (CSI), a process that causes calcium scaling and comes as a result of high pH levels.
Can You Safely Swim in a Pool With High Alkalinity?
As long as you have enough chlorine in your pool (around 3ppm for total chlorine) and the pH level is balanced (between 7.4 to 7.8), then a pool with high total alkalinity is still safe to swim in. You should, however, balance TA as soon as possible because it can lead to calcium scaling and cloudy water—a breeding ground for bacteria.
Takeaway Key Points
- Total alkalinity should only be lowered when it causes a significant rise in pH levels, or when it causes calcium scaling through CSI.
- To lower pH and total alkalinity, use a strong acid such as muriatic acid, sulfuric acid, or sodium bisulfate, all of which lower both pH and TA, but at different rates.
- You need to use an accurate water test kit that can give you correct readings. If possible, find software that can help you get exact amounts of dry acid to add into the water.
- This process may take longer than anticipated, depending on how high pH or total alkalinity is and how low you need to bring them down before the aeration process begins. However, you can always use an air compressor or any other aerator to accelerate the process.
- If you have achieved the ideal reading for total alkalinity but the pH is scaling up because the process of aeration has not yet ceased, you can use borate to keep the pH stable. The recommended level for pH is around 7.4 or 7.6.
This article is accurate and true to the best of the author’s knowledge. Content is for informational or entertainment purposes only and does not substitute for personal counsel or professional advice in business, financial, legal, or technical matters.
Questions & Answers
Question: Alkalinity 220 and pH 6.8.added 15 pounds pH + still reading 6.8 ph? I have 23,000 gallon pool. How much borax and Muriatic acid do I need to add?
Answer: First of all, I am interested to know which test strip you are using because the variance between pH and TA is not real. In that kind of high TA, your pH is expected to be high too since by default high TA raises pH and your test kit might not be accurate. I recommend you use the Taylor test kit or Lamotte ColorQ Pro test kit that will give you exact readings of chemicals in your pool. However, if your pH is low and TA is high, use borax to raise your pH to around 7.8 if you can't aerate your pool, then add Muriatic acid slowly by slowly to reduce both pH and TA but don't let pH go lower than 7.2. If your TA is still high, repeat the process until your TA is lowered between 80 and 120.
Question: I have a 10,400 gal 21’ round pool. The TA is 240, but the Ph is 6.8 . How much 20 mule borax do I use first to raise the PH? How much muriatic acid? I put too much shock in a few days ago and it is reading 8-10.
Answer: A half pound of Borax raises the pH of a 10,000 gallons pool by 0.1: You can use the measurement to find how much Borax you need to raise your pH to a given number then add muriatic acid as directed to lower both pH and TA. You may have to repeat the process till pH and TA balance.
Question: My pH is 7.2, my alkaline is 150. How much borax do I add to 11,800 gallon pool?
Answer: 1 box of borax will increase pH in a 20000 gallon pool by 0.1, meaning your pool will need around 2 to 3 boxes of borax and then carefully add muriatic acid to bring down both pH and TA since your TA is a little higher. Alternatively, you can aerate the pool using foutain adapter or eyeball fitting to bring up pH levels to around 7.6 and then reduce both the pH and TA using muriatic acid. TA should be between 80 to 120ppm for liner pools and 100 to 125ppm for plaster pools.
Question: what is pH?
Answer: pH is the level of acidity or alkalinity in a solution. 7 is the neutral value. The lower you go from 7 the more acidic your solution will be, and the higher you go from 7 the more alkaline the solution will be.
Question: I have a 10,000 gallon in ground vinyl pool. The water is extremely "hard" and the total alkalinity is too high (around 200). However, my PH is also very low at 6.7. How can I have a low PH and a high TA ? And, I guess, more importantly, how do I correct this. We already added muriatic acid to lower the TA, but it only came down from 200 to 180, while the PH went from 6.9 to 6.7.
Answer: You need to add borate in your pool to raise pH to around 7.6 first before adding Muriatic acid since your pH will go dangerously low.
After raising your pH, add Muriatic acid carefully as you test both pH and TA levels, don't let your pH go below 7.2 this time. TA should be between 80ppm to 120ppm.
If the TA is still high and pH is getting down to 7.2, repeat the process of adding borate to raise pH then adding Muriatic acid to lower both pH and TA to recommend levels.
Question: My pool is 5500 gallons. The alkalinity is 427 ppm and PH 8.5. I put one gallon of muriatic acid and tested the water after 24 hours, and there was no difference in the levels. The free chlorine is 0.05 ppm. Should I add another gallon of muriatic acid, or should I shock it, wait 24 hours and then add more acid?
Answer: Don't shock the pool until pH and Alkalinity are balanced. Both your pH Alkalinity are still too high: Just add more muriatic acid to bring down TA between 80 - 120 ppm, pH between 7.4 - 7.6. If your pH goes below the recommended range, you will have to use 20 Mule Team Borax to raise the pH levels without raising TA, and repeat the process till your pH and TA are balanced then shock the pool for free chlorine to read 3 ppm.
Question: My fiberglass pool holds 20,000 gallons and the TA is around 300ppm, but the PH is always between 7.3 to 7.6. I have tried to reduce TA with muriatic acid for a couple of months but adding it just decreases the PH and the TA stays the same. What do you suggest I do?
Answer: Just use muriatic acid to reduce the TA down to normal, pH too will reduce but that is not a problem because you will use aeration process to bring back pH to normal. Refer to the same article on different ways you can bring back pH through aeration. The first one I prefer is natural method where you just leave the pool pump running after adding muriatic acid and the TA is already back to range then the pH will rise back to normal within 24 hours. The second method is where you accelerate the process by using aerators such as water fountain equipment or fitting jets to expose more pool water for aeration.
Question: Ph is 6.8 TA is 180. How much Borax to use to bring up ph in my pool?
Answer: The best thing to do is to find a borate test kit and add small amounts while testing your pH and borate levels. Borate should be in the range of 30 to 50ppm and not more. You can also use a pool calculator to determine what amount your pool need. But generally, borate has around 9.5 pH which is very high and you will need to add it in small amounts while measuring your pH levels.
Question: My plaster pool's TA crept up from 120 to 130 over the last few weeks, but the pH is a low 6.8 to 7.2 maximum. How much Mule Team Borax should I use to lower the TA for a 14,000-gallon pool?
Answer: Your TA is not very bad, and you will not need much muriatic acid to lower it to settle between 100 - 120 ppm. But since your pool's pH is already down and will further go down when muriatic acid is added, add 20 Mule Team Borax as directed by the manufacturer to raise the pH first up to around 7.8 then add muriatic acid to lower both pH and TA down to recommended levels.
Question: I have a 29,000-gallon inground pool. Recently, my alkalinity was measured at 240, with a pH of 7.8. I added muriatic acid, and the pH dropped to 6.8, while the alkalinity dropped to 180. I'm not sure what to do now. Any advice you could give would be much appreciated. I see that you recommend borax in other postings. If that is the case, how much should I add?
Answer: Alkalinity level is still too high, but your pH is going down past the recommend the lowest level of 7.2 for a standard swimming pool. As such, you need to add borax to raise pH first to around 7.8, then add muriatic acid to bring both the pH (7.4 - 7.6) and TA (80 - 120ppm). For the amount of borax to add, use the ratio given by the manufacturer.
Question: I have high total alkalinity and low ph - this is the most comprehensive explanation of what is happening and how to solve it Thank You! My plan is to point the return up for aeration on the surface - I never thought of that, and I have not been patient enough. If not successful, my next step will be to try borax - is this correct?
Answer: Yes, use aeration to raise your pH because it will not affect your TA and it will be more stable when it rises naturally, but be a little patient as it might take long depending on the level of your pH. If it takes too long for pH to rise, use borax to raise pH to around 7.8, then add Muriatic acid to lower both the TA and pH but be careful for pH not to go lower than 7.2, repeat the process until your TA is lowered to the recommended level and pH is stable between 7.4 and 7.6.
Question: I just recently had an above-ground, 8,600-gallon pool installed. Right away I noticed that the TA was extremely high. Over the last two weeks, I have added three quarts of diluted muriatic acid one quart at a time every three days or so. Twelve hours after the last treatment I am still sitting at around 230 total alkalinity. This doesn’t seem to bring the desired results . Do you have any suggestions? The PH is also still high.
Answer: For faster results, you need to use a strong acid and not a diluted acid. Try using a strong muriatic acid instead of a diluted one, and both pH and TA will reduce.
Question: I added sodium bicarbonnate at required level a hour ago can I free chlorine shock my pool now?
Answer: Yes, one hour is more than enough, you can shock your pool to raise free chlorine level.
Question: I have an above ground pool. The TA is very low, but the pH is very high. What do I do?
Answer: You will need to add pH Reducer first to take the pH down between 7.4 and 7.8, After that, add Alkalinity increaser until the TA reads 80 - 120 ppm for liner pools, and 100 - 125 ppm for plaster pools.
Question: I'm in the process of stabilizing my chemical levels in our pool to get it ready for the season. My ph is at 6.7 and the TA is at 150. Using an AquaChek digital tester. I also double-check the reading with test strips from In the Swim, which is also made by AquaChek. What should I do to lower the TA and get the PH to it's proper range?
Answer: Use borax(borate) to raise pH on the higher side around 7.8 (borax will not raise TA), then add Muriatic acid to lower both pH and TA.
Be careful when adding Muriatic acid by measuring your pH and TA levels frequently as you add the acid; pH should not go below 7.4 and if your TA is still high after adding Muriatic acid, repeat the process until TA is between 80ppm to 120ppm and pH between 7.4 and 7.6.
Question: How often will I have to repeat this process?
Answer: If the pH and TA levels are not balanced properly, you will have to repeat the process until they balance out.
Question: The pH is 7.8 and TA is 240 ppm in my above ground pool. What do I do?
Answer: Add Muriatic Acid to lower both the pH and TA: Your TA should be between 80 - 120 pmm. You need to be very careful while adding muriatic acid since the pH may go down the recommended level that is 7.2 - 7.8. However, it is likely that pH will drop below 7.2, if so; just add 20 Mule Team Borax to raise the level of pH back to the recommended level, don't use pH plus since it will raise the TA level too. You may have to repeat the process if your TA is still high after adding muriatic acid.
Question: I have a 21,100-gallon pool, just painted and freshly filled. I'm having trouble lowering my TA, it's at 210 but pH is at 7.6. I've already added 13lbs of dry acid. And the TA doesn't go down at all. Not sure what else to do?
Answer: Which dry acid are you using? I recommend Muriatic acid as it faster in lowering both the TA and pH. Carefully pour right amount of Muriatic acid evenly around your pool. Your target TA should be 100ppm, pH is okay but when you add Muriatic acid it will go down. If TA is balanced but your pH goes down below 7.2, use 20 Mule Borax to raise the pH to recommended levels or just leave the pool running for 24hrs to aerate naturally and the pH will rise by itself. If the TA is still high after 24 hrs of adding muriatic acid, repeat the process by adding more Muriatic acid and raising the pH using aeration or Borax. You can find Muriatic acid and 20 Mule Team Borax here: https://dengarden.com/swimming-pools/Lowering-Tota...
Question: How do you know how much borax, per gallons of water? I have a 24000 gallon in-ground vinyl pool.
Answer: 40 ounces of Borax increase pH in a 5000 gallons pool by 1ppm. Means you will need 192 ounces of borax to raise it by 1ppm in 24k gallon pool.
Question: I have a 608 gal paddling pool. the TA is between 120-180, PH 7.2, how can I get the TA to the right level without affecting the PH level?
Answer: There is no single chemical to lower TA without affecting the pH. However, you will have to raise the pH to around 7.8 first using 20 Mule Team Borax, which doesn't affect your TA, then add Muriatic acid slowly by slowly to lower both TA and pH. Be very careful so that pH doesn't go below 7.2 when adding Muriatic acid. Your target is to lower TA between 80 and 120, when pH is 7.2 but TA is still high, repeat the process of raising pH and adding Muriatic acid until you reach your target TA and pH should range between 7.2 and 7.4.
Question: My pool's total alkalinity reads 1000 ppm, chlorine levels are high, and pH is low. What do I need to do to balance the chemicals in my pool?
Answer: First, you need to stabilize pH and TA. The level of TA is too high; which calls for a lot of work. You need to raise pH first to levels higher than recommended, then add Muriatic acid to reduce both pH and TA. You will repeat the process until you balance TA and pH.
For chlorine, you can leave it to reduce by itself as free chlorine will be used up by sunlight until it reaches the required limit, then shock the pool when free chlorine is below 3 ppm.
Question: I recently had an in-ground, 13,300 gallon, saltwater pool installed. I have been working to lower my TA and pH with muriatic acid. I've added over a gallon over the last week or so, but now my TA is reading 60-70ppm while the pH is still holding at 8.0-8.2. I'm afraid to continue to add muriatic acid and cause my TA to drop even lower. What can I do to bring the pH down to an ideal range and get my TA back up to the ideal range as well?
Answer: You will have to raise your total alkalinity using alkalinity Increaser to around 125ppm, then add more Muriatic acid to lower both pH and TA. TA should read between 80-120ppm and ideal pH level between 7.4 and 7.6 , if pH is still high and TA is out of range, repeat the process by raising TA and adding Muriatic acid to lower both pH and TA.
Question: I have a 17,300 gallon above ground pool. I can't seem to get my ph and alkalinity down to readable levels. What should I do?
Answer: Add Muriatic acid to lower both pH and TA. While adding the acid, make sure you do it slowly in small portions while measuring pH and TA so that pH doesn't go below 7.2 and doesn't go below 80ppm. If your pH is down to 7.2 but TA is still high, add borax to raise pH to around 7.8 then add more Muriatic acid to lower both levels. Repeat until TA is within the recommended range of 80 to 120ppm and pH is between 7.2 and 7.4
Question: PH is 8.2 and TA is 110. I am confused from all the various comments and questions as to what I need to do to get it all balanced? Salt water pool. 18,000 gal in ground.
Answer: Add Muriatic acid to lower pH between 7.2 and 7.8. Your TA is not bad but adding Muriatic acid will lower it together with pH. Don't let TA go below 80ppm; you can raise TA using Alkalinity Increaser if it goes below 80ppm.
Question: I have a 50,000 litre concrete pool, my TA 70 and Ph 7.8.. if I add muriatic acid to reduce the PH how do I increase TA?
Answer: You need to raise your TA first since it's already too low. Add alkalinity increaser so that your TA reads over 100ppm, then add muriatic acid to lower both pH and TA. TA should never go below 80ppm.
Question: I have an above ground pool. The TA is high and the ph is at 7.2. I have done soda ash and muriatic acid but just end up in the same mess. What can I do?
Answer: Your pH is a little down: Add 20 Mule Team Borax to the pool to raise pH level higher (around 7.8) first, then add muriatic acid carefully to bring down both the pH and TA. You may have to repeat the process till TA and pH balance out, depending on the level of your TA; the higher the TA, the more you'll have to repeat the process.
Question: Please help me. I breed catfish at home but the larvae after hatching begin to die slowly. Is it because of high TA which is 188ppm ?
Answer: TA affects pH levels; high TA raises the pH and low TA reduces the pH. Check that your pH is not above 11 and should no go below 4 as these levels are not ideal for fish rearing and might be causing larvae death. Control your pH and TA will be fine, the ideal range for fish is 6.5 - 7.5.
Question: I have an 18'x4' round above ground pool, pH: 6.8, TA: 180. How do I get my pool's pH to 7.4 and TA to 120?
Answer: You need to raise the level of pH to read between 7.8 - 8.0 first using 20 Mule Team Borax or through aeration without raising the TA, then carefully add muriatic acid to lower both pH and TA to recommend levels. If your pH goes down the recommended range, you will have to repeat the procedure again till both pH and TA balance.
Question: I have been working to lower my alkalinity, and I got it to a 1.5, and it has gone back up to a 200. This is the second time I have tried to lower it, and it goes back up before I am finished lowering it. What am I doing wrong?
Answer: Are you using muriatic acid? This acid should work well in lowering both TA and pH. Then raise the level of pH back to normal using aeration.
Question: Our saltwater pool used to feel wonderful. Soft salty water and now it is not the same. We used to put 6-7 bags of salt in once or twice a month, the new company rarely puts salt in and when they do it’s only 1 bag. My pool is roughly 100,000L. Should we be putting more salt like before?
Answer: Salinity should always be between 2500ppm and 3500 ppm, make sure it's always within the range because excess salinity means draining potion of your pool water and replacing with fresh water.
Question: I checked my pool, and the pH just right, but the alkalinity is high. What kind of solution should I put in the pool?
Answer: You need to add Muriatic acid to reduce the TA, but remember that any acid will lower the level of the pH too. So the best thing is to add Muriatic acid to the pool to lower the TA down between 100 - 125 ppm, then add 20 Mule Team Borax to raise the pH to the recommended levels between 7.2 and 7.8. This might take a couple of days, remember to take accurate readings while fixing the problem.
Question: We use a frog filtration system. Is borax ok to use with this system?
Answer: Yes, it is OK since borax will not affect your system.
© 2015 Barack James
Barack James (author) from Green City in the Sun on August 25, 2020:
Borax should always read between 30ppm to 50ppm, the best thing to do is to add borax slowly by slowly while measuring your levels.
For Muriatic Acid Dosage: 1.95 qts reduces TA by 20ppm in a 15000 gallons pool, you should also add muriatic acid slowly while testing your pH so that your pH level do not go lower than 7.2 and repeat the process until TA is within the range of 80 to 120ppm.
Courtney on August 25, 2020:
I have been fighting with a low ph (6.8) all summer my alkalinity is also high (240). I added borax last night to increase the ph and then I was going to do the muriatic acid to lower ph and alkalinity. Can you tell me how much borax and muriatic acid to add for a 15000 gallon above ground vinyl pool? I use the Clorox xtra blue chlorine tabs in the skimmer and I have heard this can case issues?
Barack James (author) from Green City in the Sun on June 26, 2020:
Good you have no metals in your pool being that you are using well fillwater. Start by lowering the pH and TA to recommended levels using Muriatic.
The milky water is due to low chlorine in your water and you need sufficient liquid chlorine to clear the chloramine that is making your water cloudy.
Melinda Lindsey on June 25, 2020:
Heres you a big pool mystery
We have 10000 pool, filled well water. We have high ph water. But no iron! More like great spring water. Anyways filled pool shocked it. Next thing tested, at home and at local pool company. Ph 8.4 or more, TA 249 or more. Add acid so far 2 gallon over a weeks time. Both came down very little. Waited a day shocked it. Tested again still high. And water is so milky... We clean, vac over and over I added 2 cups of clarifier because the vac just picks up the crap that is like milky very fine dust and puts it by in the pool. Tonight I am going to add another half gallon of acid. Fingers crossed!
And we have Type A filter, cleaning it every 2 to 4 hours. This issue is driving me crazy! Ive tried everything. Should we add the chemical that makes that bond to bigger pieces at the bottom of the pool and then vacuum to waste? Because we will still be adding well water if we have to replace it???????omg
Barack James (author) from Green City in the Sun on August 15, 2019:
"...there is no pool chemical that can lower pH without lowering TA". This is because any strong acid like Muriatic acid or any pH minus with acid will lower both pH and TA. That should be the correct statement. Borax will raise pH without raising TA. Thanks!
RZ on August 15, 2019:
Your article says "Unfortunately, there is no pool chemical that can raise pH only without raising total alkalinity—maybe one day chemical engineers will invent that kind of chemical :)" but later says "use 20 Mule Team Borax to raise the level of pH without raising your TA." Could you please clarify?
Barack James (author) from Green City in the Sun on August 02, 2019:
Hello Susan, it's true Muriatic acid will lower both pH and TA. I suggest you raise TA first because it's way below recommended range of 80 to 120ppm and if you add acid it go down further. Baking soda will increase pH also but not so much, so you will need to raise TA slightly higher than 120ppm so that when you add acid to lower both, TA will not go lower than 80ppm. It's a lot of work but that is the only way you can get it done.
Susan A Newton on August 02, 2019:
Update; TA is 60
pH is 8.2
chl is .5
This is what the pool calculator is saying to do......
Add 31 fl oz by volume of Muriatic Acid - 28.3% (18°) Baumé.
31 fl oz is 3 cups 7 fl oz .
Note: pH calculations depend on TA and Borate. Changing pH will also change TA.
TA suggestion is.....
Add 236 oz by weight or 188 fl oz by volume of baking soda.
236 oz is 15 lbs 0 oz.
188 fl oz is 1 gallons 2 quarts .
NOTE: Adding baking soda will raise pH.
I'm at a loss, If I do either they move. Any suggestions would be a great help. Thank you
Barack James (author) from Green City in the Sun on July 31, 2019:
Okay, meanwhile you can keep adding chlorine to keep algae and ammonia away.
Susan A Newton on July 31, 2019:
UPDATE : Well I went and tested the water again and I think I'm getting bad reading from the test strips . Here are some of the readings.
This is just today,
TH TC FC PH TA Stabilizer TIME of DAY
250 0 0 7.8 240 50 10:35am
250 0 0 6.8 180 50 10: 38 am
110 1 0 6.8 180 50 10:58 am
250 0 0 7.8 180 50 2:24 pm
110 0 0 6.8 240 50 2:29 pm
250 1 0 7.8 180 50 2:36 pm
I went and bought a new bottle of clorox Test strips I tested with.
The same readings as the other test strips , I even called the company and asked why is this bouncing all over the place ? They said it might be a bad batch. I said both of them, with different batch #'s ? I ordered a Kit from Amazon a Taylor Deluxe. It will be here this Friday. I will test it then. But I can't treat my pool until I know the true reading. I'm at a loss as of right now. But I will Let you know what the reading are and if the test strips were giving a bad reading.
Barack James (author) from Green City in the Sun on July 31, 2019:
Hello Susan, if you added muriatic acid TA should be moving down. Which test kit are you using? There could be problem in your chemical measurements or you are not adding the right amount of Muriatic acid to lower TA between 80 and 120ppm.
Draining and refilling portion of your pool water should be the last option just to lower TA because strong acid should lower it. However, if unable to get it down using Muriatic acid, you can go ahead and drain portion of your water and refill with fresh water, then start balancing your chemicals. Also, with your FC at 0ppm, you are risking developing algae and ammonia and you should work hard to balance your chemicals soon then shock your swimming pool.
Susan A Newton on July 31, 2019:
Hello Again Barack,
I still can't get the TA to come down. It never moved from 180. I Use the Pool Calculator . My PH was to start 6.8 , TA 180. I entered the readings to the Pool calculator and followed what to do. I added borax to the pool. It took the Ph up to 8.4 and then I used Muriatic acid the next day. Just what the pool calculator advised me to do. I tested it 6 hrs later the PH was 7.8 . Today I just tested the pool and the reading are,
Total hardness 110
Total Chlorine 0
Free chlorine 0
PH 6.8 ( I tested 6 times in different places)
TA 180 ( It never moved)
Since the first time I posted a question to you I have been trying to get the TA down and ph up to make them stable. I'm having trouble with both . I even have been using a fountain to aerator to keep the PH up. What am I doing wrong? I have done this 3 times and still no luck on the TA . I can bring the ph up and down but not the TA. I use the sticks to test the water . If that is any help. Should I empty the pool refill it? I have use well water to fill it. Help Please. Thank you for any and all help .
Barack James (author) from Green City in the Sun on July 26, 2019:
You can swim as soon as your pH and TA are balanced. Good work Susan, just add Muriatic acid and borax a couple of times and your TA will come down to recommended levels. Nice weekend.
Susan A Newton on July 26, 2019:
Thank you Barack, I did raise the PH to 7.8 the TA is still 180. Once I get them both to where they need to be , how long before we can swim, Tomorrow? I live in S.C. Again Thank you . Have a beautiful weekend.
Barack James (author) from Green City in the Sun on July 25, 2019:
There is no way to lower TA without lowering your pH. The best thing you can do is raise your pH first up to around 7.8 using Borax that will not raise your TA, then add Muriatic acid to lower both pH and TA. You need to be very careful not lower your pH below 7.2. If your pH has 7.2 but TA is still high, add more borax to raise your pH again up to around 7.8, then add Muriatic acid to lower both once more till you get your TA within the range. Repeat the process of adding borax to raise pH and Muriatic acid to lower both until you balance your pH and TA.
Susan Newton on July 25, 2019:
Hi, I have an vinyl in ground pool 16'x 40' 6' deep 4' shallow end.
I.m having issues with high TA 180 and low PH 6.8. I seen where you said to accelerate the aeration process. what does that do ?. I want to know how to lower my TA without lowering my PH anymore then it is. I read about using Borax with out upping the TA, Is that True? I just need to know what I have to do. Thank you.
Barack James (author) from Green City in the Sun on July 19, 2019:
Muriatic acid should help in reducing both the pH and alkalinity. You need to be very careful not to lower your pH below 7.2. If your pH has reached down to 7.2 and Alkalinity is still high, add 20 Mule Team Borax to raise pH higher around 7.8 then add more Muriatic acid to lower both until both are balanced.
Kate on July 19, 2019:
Hi we have a spa pool ph is 8.4 alkalinity 240
We have just cleaned and refilled spa following instructions we were given
How do we get both down to good levels
We got oh increase and decrease and alkaline up
What else should we buy
Barack James (author) from Green City in the Sun on June 15, 2019:
No, those levels are too high. Total Alkalinity(TA) should be between 80 to 120ppm and pH between 7.2 and 7.8. Use muriatic acid to lower both TA and pH between the the recommended range. Add muriatic acid slowly by slowly so that your pH doesn't go below 7.2. If the TA is still but pH has reached 7.2, use 20 Mule Team Borax to raise the pH to around 7.8 and add more Muriatic acid till both are balanced.
Steve on June 14, 2019:
Alkalinity is 200ppm ph is 8.0 is this ok
Barack James (author) from Green City in the Sun on September 19, 2018:
Hello Frenchfrey, your alkalinity is too low, use a different alkalinity increaser like the one by Pool Mate you can find on Amazon through a link in the same article. But first work on balancing the pH using a pH reducer, then lastly balance out your TA .
Frenchfrey on September 19, 2018:
I have an in ground fiberglass pool. All summer my total alkalinity has been low (around 50) while my ph has been very high. I have tried using alkalinity increases which also raises my ph, and then ph down which then brings down my total alkalinity. Very frustrating. Any help would be appreciated.
Barack James (author) from Green City in the Sun on June 11, 2018:
Your pH is too low and TA too high: You need to bring down the TA using Muriatic acid. But since muriatic acid will further bring down the pH level too; you first have to raise the pH level up to around 8 using 20 Mule Team Borax (not pH+) - and then carefully add muriatic acid to bring down both TA and pH. TA should read between 100 - 125 ppm for plaster pools and pH between 7.4 - 7.6. If your pH goes down below the recommended levels and TA still high; you will have to repeat the process till they both balance out. You can find 20 Mule Team Borax and Muriatic acid on Amazon through the links in the same article. Good luck Roy!
Roy Paap on June 11, 2018:
my pool is very clear i have a aquacheck didgital tester the chlorine reads ok the ph reads 6.6 and the alk reads high at180 how do i fix it to be right my pool is inground plastered and old paint is flaking off thanks for any suggestions roy
Barack James (author) from Green City in the Sun on September 03, 2017:
Hi Cottpool, thanks for your comment. Either of the test kit is just OK. However, Lamotte colorQ pro 11 can do a few more tests including copper, iron, and biguanide; which are not very important pool chemical tests and you can do without. So the choice will depend on the amount you are willing to spend on a pool water test kit.
Cottpool on September 03, 2017:
Thanks for sharing. Good information to use for pool maintenance. Will follow your advise on the LaMotte ColorPro Kit. I noticed there are versions 9 & 11 which are for both pool and spa. What are your recommendations?
Barack James (author) from Green City in the Sun on July 13, 2017:
Rosa, seems you have a lot of work here. The pH is very low, don't add more muriatic acid because pH will go much down and may cause more problem like corrosion and metal staining. Just leave your pool to aerate for at least 2 - 3 days without adding any chemical while your pump is on 24/7 for the pH level to rise up above 7.6 ppm by itself.
Also, if you can find and use any aerator like pool water fountain equipment, please do so that you speed up the process of raising the pH level first. Once you get your pH higher, you can then use muriatic to lower both the alkalinity and pH. This time, you will need to watch on the level of pH while adding muriatic acid so that pH does not get below 7.2 ppm. That means you will have to repeat the process until you get your total alkalinity down to recommended level that is 80 ppm to 120 ppm. Alternatively, you can use 20 Mule Team Borax (on Amazon link above) to raise your pH without raising TA and then add muriatic acid to lower both.
Finally, since you are using well water in your pool, when you are done balancing your pH and TA, remember to add Borate in your pool to help keep the pH stable so that it does not drift down again. Here is a link to how you can add Borate in your pool: https://dengarden.com/swimming-pools/Adding-Borate... - Please feel free to ask more questions or communicate your progress here as you work on your pool. Good-luck!
Rosa on July 13, 2017:
Ph is 6.8 and alkalinity is 240 ive added muratic acid twice and doesnt seem to be going down i do live in county so i have well water
Barack James (author) from Green City in the Sun on July 13, 2017:
Hi Rosa, what is your pH reading? The pH must be high too. You need to add more muriatic acid to farther lower both TA and pH, then give your pool time to aerate in order to raise the pH level. Please take readings for both TA and pH after 24 hours and not immediately as this process may need more time to get perfect balance of TA and pH.
Rosa on July 13, 2017:
I have tried to get my pool levels to the correct level and ots just not working im not sure what else i can do i have put muratic acid in my pool and alkalinity is still way too high mt pool watwr is very cloudy and im not sure what else to do!
Barack James (author) from Green City in the Sun on June 05, 2017:
Magnum that is true, Super Floc is the solution for a cloudy water caused by lots of debris. It is perfect for spring start-up when pools have lots of dirt common in the spring seasons. Floc has a fast-acting formula that drops debris to the bottom of the pool for easy vacuuming. Super Floc is also safe for all pool types and works with all filter types.
Magnum Wessell on June 05, 2017:
Lanea head use a floc such as drop out to settle the cloudy water to bottom then vacuum out
Barack James (author) from Green City in the Sun on April 29, 2017:
Hi, Lanea Head, from my understanding, your pool is still under control, all you need is an accurate test kit (See:https://discover.hubpages.com/living/Lamotte-Color... ) since there is a high chance that the chemicals (PH, CH, TA, etc) are not well balanced in that pool. Also, ensure that your filtration and circulation system is perfect (not stagnant). You can follow this link for more options you can use to identify the cause of cloudiness and how to clear your cloudy pool water: https://dengarden.com/swimming-pools/Cloudy-Swimmi...
Lanea Head on April 28, 2017:
I just opened our 30,000 gallon above ground pool for the summer.
It was yucky green with lots if algae. I brushed the walls and the bottom then vacuumed it. Later that night I shocked it (heavily) and put 3 chlorine tablets in the skimmer basket, and poured 2 gallons of liquid chlorine into the water . The next morning the the green was gone but the water was very cloudy. I vacuumed it really well and let the filter do its job for a few days thinking it would clear up but it is still cloudy. Now two weeks later it's still cloudy. Last night I shocked it again using more shocked than needed. I get up this morning and it's still cloudy so I vacuumed it and now I have the filter running. It's not as cloudy as it was to begin with I can see to about my third pool step. The test kit that I use only measures bbr, chlorine, and pH. It says my pH is low and my chlorine is high. Do you have any tips or advice for me? I have for kids that are waiting on this swimming pool and I can't seem to clear it up