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How to Raise pH in a Hot Tub: the complete guide

Increasing the pH in a Hot Tub

Hot tubs are meant for relaxing, chilling out and allowing the stress of the day to melt away totally. However, if you have issues with hot tub pH and general chemical imbalance, it might affect the amount of relaxation you can actually get out of your hot tub. Raising the pH level of your hot tub is key if your pH levels have dropped too low however, keeping your hot tub pH levels balanced generally is vital. Therefore, in this article, we are going to talk about hot tub pH, it’s importance, how to raise pH levels and how to generally balance the pH levels in your hot tub. 

One of the reasons why pH levels are vitally important is that when they are not balanced, you can end up with a cloudy swimming pool, or scale problems and even worse, algae. Therefore, it is necessary to keep an eye on pH levels and make sure they are balanced. 

Why is Hot Tub pH Important? 

If you listened carefully in your high school chemistry class then you will remember that when you mix a chemical with water and there are more hydrogen ions, then we say it is acidic, however, fewer hydrogen ions is referred to as basic. 

When measuring pH levels, you want to achieve 7 or more, this is classed as neutral. However, anything less than this and you are reaching acidic territory. The goal is to reach around 7.5 on the pH scale. You don’t want your pH levels to be too high or too low, either way, expect to experience problems in your water. 

Low pH Levels 

When you have low pH levels, it could cause massive issues. For example, lower than 7.4 is not a good thing when it comes to your hot tub water. The reason why you don’t want low pH levels is that low pH levels means high acidity, and high acidity is most certainly not a good thing when it comes to your hot tub. When the water in your hot tub is acidic, it reduces the effectiveness of water sanitizers, this is definitely not a good thing because it essentially means that there will be more bacteria in your hot tub water. 

One other reason why you want to keep an eye on your pH levels and make sure they do not go too low is that it can cause corrosion eventually. Corrosion is one of the worst things that can happen to your hot tub components. 

High pH is also not a good thing, anything higher than 7.6 on the pH scale is considered high. This would mean that the water is at a “basic” level, when your pH levels are too high, it also reduces the effectiveness of the sanitizer, making the hot tub more prone to bacteria overgrowth. You might also notice that your hot tub water looks slightly cloudy, this happens when the pH levels are too high.  

What is Total Alkalinity? 

There are a number of factors to consider when dealing with pH issues and alkalinity is one of them. What exactly is total alkalinity or TA as it is often referred to? Total alkalinity is basically neutralizing acids, how effectively a solution can neutralize or counteract acids is the total alkalinity. 

Total alkalinity in your hot tub actually focuses on balancing the overall pH levels in your spa water. The whole point is being able to balance pH levels without disturbing the total alkalinity and without totally destroying the chemistry of the hot tub water. 

One of the most crucial tests is to measure and adjust the total alkalinity. The goal is around 140 parts per million. Use alkalinity increaser to fix alkalinity problems, use it in moderation first to check its effectiveness, then add more if there has been little or no change. Once you have managed to balance out the total alkalinity, this is when you can start to work on the pH levels. Sometimes fixing the total alkalinity can actually fix or balance out your pH levels. 

Balance Your Hot Tub’s pH Levels 

When your pH levels are too low, the water is classed as acidic, mostly you would add alkalinity solutions to help raise the pH. With basic water, you need to put acids into the water to reduce the pH levels. This is the most common cause of action however, this might also cause some issues with the total alkalinity. Balancing things out can be difficult because it is still possible. Now, let’s talk about how to increase the pH levels in a hot tub. 

How to Raise the pH in Your Hot Tub 

pH increasers usually consist of various chemicals including sodium carbonate, which is often referred to as soda ash. This is the close cousin of sodium bicarbonate or baking soda, this can actually be used to raise pH levels in your hot tub however, it is not as potent as soda ash. Sodium bicarbonate is effective when it comes to increasing the total alkalinity, it works well to raise the total alkalinity without affecting the pH levels. 

You should also bear in mind that soda ash can sometimes raise the TA. Therefore if the pH is slightly lower and the total alkalinity is relatively high, sodium carbonate could possibly raise the alkalinity a bit too much. Soda ash can also cause cloudiness in the water therefore if you do utilize soda ash to reduce pH then you would have to work on reducing the cloudiness when you are done. 

How to Reduce the pH in Your Hot Tub 

You can use a pH decreaser to reduce the pH of your hot tub water. The main component of the pH decreaser is sodium bisulfate. As well as decreasing the pH of your hot tub water, it will work on decreasing the total alkalinity too. Therefore, once you have reduced the pH levels, you would also need to work on bringing your total alkalinity back up once you are done. 

Sodium bisulfate can balance out pH levels as well therefore if you want to balance out your total alkalinity, it won’t throw your pH levels off too. 

You can also use muriatic acid to reduce your pH levels and to balance out the total alkalinity. Be careful when you are using muriatic acid however because it is a very potent substance. To avoid burning your skin or eyes, make sure you wear goggles and acid-resistant gloves. Also, be sure to wear long pants, long sleeves, and full shoes when you are using it. 

Bear in mind that when you are using muriatic acid, you should mix it with water first. Turn the jets on to allow the acid to mix with the water overnight. Once you have done this, test the water to check the levels. 

Starting Again 

Sometimes, it might just be best to drain the water and start again. This might be necessary if you spend a lot of time increasing or decreasing the pH levels. If you choose this option, one day prior to draining the water from your hot tub, use line flush to flush out the system to eliminate any substances that might be wreaking havoc with your hot tub chemistry. 

Bear this in mind, if you get your water from an outside water source, there could well be a high level of chlorine in the water. Also, there could be various metals in the water which could cause hard water issues. Once you have drained out your hot tub, wash the inside of the tub thoroughly, do not leave behind any residue. 

To prevent issues, do the following things: 

Utilize a Hose Filter 

Filter out the metals and other chemicals that might be contaminating the water by using a hose filter. It won’t remove all the contaminants, but it will remove some of them. 

Utilize Metal Sequestrant 

A hose filter is effective in filtering out some metals and contaminants but it certainly won’t be able to do this for everything. Therefore, you might need to utilize a metal sequestrant, they work by attaching themselves to the metals, this essentially facilitates the filtration process. 

Make sure you use testing strips to test the chemicals in the water before you introduce any new chemicals to the water. 

To conclude

Balancing pH levels is a very important part of hot tub maintenance. You will have to regularly test your pool chemistry to ensure that nothing is out of whack, however, be mindful of the chemicals you do add to your hot tub water because some chemicals throw certain things off such as the total alkalinity or the pH levels. 

When your pH levels are too high, it causes acidity reducing the effectiveness of certain sanitizing chemicals. Therefore, if you test your pH levels and they are indeed too high, make sure you take action quickly. Soda ash works well to reduce pH levels but make sure you check your alkalinity levels first. 

Posted in pool maintenance

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