1. How To Lower Alkalinity In A Hot Tub Without Chemicals ...
2. Why Hot Tub Alkalinity Matters - How To Balance A Hot Tub ...
3. How Much Muriatic Acid To Lower Ph
4. Adding Muriatic Acid To Pool Water

Hot tubs can be a great investment, hence the need for proper hot tub water care. Otherwise, you will experience unbalanced alkaline levels that cause the water to be cloudy and create environments for bacterial growth.

This article will help you understand hot tub alkalinity and how to keep your hot tub’s water balanced.

What is Total Alkalinity?

• To lower the alkalinity by 10ppm, you may need 1.6 lbs sodium bisulfate or 1.23 liters of muriatic acid for every 10,000 gallons of water. Sometimes, when lowering alkalinity, the pH level decreases drastically. So, to increase the pH of the water without increasing the TA, you need to use the process of Aeration.
• Dry Acid Dosage Charts (Note: ≈ 2.5 pounds of dry acid equals 1 quart of muriatic acid) Lowering pH These are very general guidelines. However, DO NOT add any more than indicated in any single application. Dry Acid for POOLS Gallons in Pool pH 120,000 60,000 30,000 15,000 10,000 7.6-7.8 11.2 lbs 5.6 lbs 2.8 lbs 1.4 lbs 15 oz.
• Lowering alkalinity If you find your hot tub has an alkalinity of above 120ppm, you need to lower it – you should aim for about 100ppm. The easiest way to lower alkalinity is to add sodium bisulfate to the water.

As a general rule, you will need 1.6 lbs (725.75 g) sodium bisulfate or 1.3 qt (1.23 L) muriatic acid for every 10,000 gallons (37.85 kL) of water to drop the total alkalinity by 10 ppm. Mix the chemical together with a small amount of water. While each chemical brand or type is different, typically you need approximately 1.23 litres of muriatic acid for every 10,000 gallons of hot tub water. This measurement will drop the total alkalinity by 10 ppm.

Contents

The first thing you want to do when balancing your hot tub water is balancing its total alkalinity first. Total alkalinity, often called a buffer, helps in balancing the pH levels. Hence, you should aim to balance the total alkalinity before you start looking at the pH levels or add any chemicals into the hot tub.

When the alkaline levels in your hot tub are unbalanced, it can have a cascade of effects on your tub’s appearance. You will also be prone to the skin to skin infection and damage.

A low total alkalinity can cause a rapid change in the pH and can be damaging to your hot tub. It can corrode metal parts and leave stains on the surface. When the pH level drops, the hot tub water becomes more acidic, resulting in burning eyes and itchy dry skin.

Another problem can result when the hot tub alkalinity is too high. High alkalinity level of the water will also cause the pH level in the hot tub to soar high, which can be difficult to lower. Such an environment can raise the calcium levels in the water, making it cloudy.

This can also result to formation of a hard, crusty mineral build-up (scale). Additionally, high alkaline water can result in green water. This is because it minimizes the effects of chlorine that help to keep algae under control.

How to Lower Alkalinity in Hot Tub

Wondering how to lower alkalinity in hot tub and stabilize the pH? Basically, the correct total alkalinity should range between 80 and 120 parts per million (ppm). A spa volume calculator can help you calculate the right range for your hot tub.

You, therefore, do not want anything above this range; otherwise, you will experience scale formation, skin and eye irritation, cloudy water, and hard to change pH.

In order to lower high alkalinity, you need to add a pH decreaser. Some of the known pH decreaser products include sodium bisulfate (dry acid) and muriatic acid. Note it is important to turn off the jets and the pump when adding the acid in order to lower alkalinity. And when you add a dry acid, place it in the middle of the tub such that the water is not circulating.

This will bring both the total alkalinity and pH levels down. We highly recommend that you retest the water after adding the pH decreaser to check if it has returned to its normal range.

How To Raise Low Alkalinity in Hot Tub

As seen above, too low alkalinity can lead to rapid changes in pH, as well as skin and eye irritation. It also causes the water to be corrosive, which affects the metal fittings in your hot tub, and this can result in discoloration of the water.

You should, therefore, aim to keep the total alkalinity readings above 80 PPM. How to increase alkalinity in hot tub? You can either use sodium bicarbonate (baking soda) or alkalinity increaser. We recommend using an alkalinity increaser that contains sodium bicarbonate which helps to raise the pH. Let the hot tub sit for 6 hours before you retest.

Conclusion

It is crucial to maintain a balanced water in your hot tub. This will keep you from problems such as water corrosion, burning eyes, itchy skin, and other serious issues. A sure way to maintain balanced water is to do frequent testing using a water test kit and then make the necessary adjustments. You can also take the water sample to a test station for results of your hot tub alkalinity level.

This way, you will enjoy your hot tub with peace of mind.

Owning a tub is a great luxury, and spending time submerged in the hot water and bubbles is the perfect way to unwind, relax and forget all the stresses of your day. However, as any hot tub owner will tell you, they also require a fair amount of maintenance.

One of the biggest jobs you have to take care of is monitoring the water to ensure its chemical composition stays just right. Part of this involves keeping the correct balance of alkalinity – so here’s a guide to how to lower alkalinity in a hot tub for when it gets too high.

If you want a preview of some of the stuff we’re going to be talking about, you can check out this video before reading on.

Why is high alkalinity bad?

Why exactly is it so important to maintain the correct balance of alkalinity in your hot tub?

If the alkalinity of your water is too high, it can lead to an imbalance in the pH value of the water (we’ll be talking more about the difference between pH and alkalinity in a moment).

This can result in high levels of calcium in the water, which in turn can lead to scaling, cloudy water and clogged filters. It also decreases the effectiveness of water sanitizers like chlorine or bromine and can even cause itchy skin for anyone using the tub.

So as you can see, it’s something you want to avoid.

What about low alkalinity?

If high alkalinity is so bad, why not just try to keep it as low as possible? Well, unfortunately, that won’t work either since low alkalinity is also not desirable.

If the alkalinity is too low, the water in your tub will become corrosive and will start attacking any metal surfaces it is exposed to. If you have water with low alkalinity, over time it will cause serious damage to your tub.

How To Lower Alkalinity In A Hot Tub Without Chemicals ...

So again, this is something to avoid. This is why you need to monitor your tub water carefully to ensure the alkalinity – you need to make sure it is not too high and not too low.

Back to school – acids and bases

Before we talk about how to lower the alkalinity of your hot tub, we need to understand something about the basics of what we are doing, and that’s going to mean talking a bit about some science stuff – but we’ll try to keep things as simple and easy to understand as possible.

From your school chemistry classes, you may remember something about acids, bases and pH values.

In short, the pH value is a measure of how acidic or how basic a solution is. Acids have pH values of less than 7, bases have pH values of more than 7 – and a pH value of 7 is neutral.

For example, coffee has a pH value of about 4.5-6, so it slightly acidic – and lemon juice has a pH value of around 2-3, making it more acidic than coffee. Hydrochloric acid has a pH value of 1-2, making it much more acidic than either.

On the other hand, eggs have a pH value of around 9, making them slightly basic while bleach has a pH value of around 13, making it highly basic. So far so good?

Alkalinity vs pH

We don’t need to lose ourselves in the science, but when we are talking about hot tub care, some confusion arises over the terms “alkalinity” and “pH”.

Perhaps understandably, some people fall into the trap of believing that alkalinity is the same as the pH level – but this is not true.

If the water in your hot tub has a pH value above 7, we can say that the water is basic, but that is not the same as alkalinity. Instead, the alkalinity of the water refers specifically to how much acid it can neutralize.

An alkali dissolved in water has the ability to neutralize acid, and the total alkalinity (TA) is a measure of how much alkaline substance is dissolved in the water. It is measured in parts per million (ppm), and tub water should ideally have a TA of 80-120ppm.

If the water in your tub has the correct alkalinity, it is more able to counteract changes in the pH value of the water and resist the effects we noted above, and this is why it is important to have water in your tub that has the correct alkalinity.

So, as we can see, alkalinity and pH are closely related, but they are not the same – for further explanation of the difference between alkalinity and pH, you can also check out this video.

Why Hot Tub Alkalinity Matters - How To Balance A Hot Tub ...

Testing – how and when

The first step in adjusting the alkalinity of your tub is testing it with a testing kit or strips. These can be bought in many department stores as well as from spa stores and online.

How Much Muriatic Acid To Lower Ph

Whichever method you use, simply follow the instructions on the pack to take a reading of your tub’s alkalinity.

As we have already mentioned, the water in a hot tub should have an alkalinity of 80-120ppm, but even if your tub’s alkalinity is perfect when you measure it, you should still continue to test it twice a week since it can change quickly. This is a very basic part of hot tub maintenance.

Remember, too, that this is just as true if you own an inflatable hot tub as a more permanent version – care and maintenance might be slightly different, but monitoring the chemical composition of the water is the same.

Lowering alkalinity

If you find your hot tub has an alkalinity of above 120ppm, you need to lower it – you should aim for about 100ppm.

The easiest way to lower alkalinity is to add sodium bisulfate to the water.

The first thing you need to do is calculate how much sodium bisulfate you need to add according to the volume of water in your tub as well as how much you need to lower the TA.

You can work this out if you know that, to lower the alkalinity of 1,000 gallons of water by 10ppm, you need to add 3.5oz of sodium bisulfate.

This would mean, for example, that to lower the alkalinity of 500 gallons of water by 10ppm, you need half that much – 1.75oz of sodium bisulfate. This is about the capacity of a large six-person hot tub. A smaller two-person hot tub could require much less.

Once you have measured out the correct amount, set your tub to circulate and pour in the sodium bisulfate. Leave it to circulate for a further 20 minutes and then shut it off.

Once the water has stopped moving, leave the tub for an hour or so and then test the water again. If you still need to lower the alkalinity further, simply repeat the steps above.

Once you reach the correct alkalinity, leave the tub overnight and then test again the following day to be sure the alkalinity is still at the correct level.

Here’s a video of a slightly different method using a special product designed to lower the alkalinity of hot tubs. Although the technique is different, the basic concept is the same.

Raising the alkalinity

What happens if you add too much sodium bisulfate and the alkalinity drops too far? In that case – or if your alkalinity drops below 80ppm for any other reason – you need to bring it back up again.

To raise the alkalinity, the procedure is the same as the for lowering the alkalinity. The only differences are what you use to do it and the dose you need.

To raise the alkalinity of your hot tub, you should use sodium bicarbonate, and the dose is 2.25oz per 1,000 gallons of water to raise alkalinity by 10ppm.

This means to raise the alkalinity of a 500-gallon hot tub but 10ppm, you need to add 1.125oz of sodium bicarbonate.

While the tub is circulating, add the sodium bicarbonate around the edges and leave for 20 minutes before turning the tub off. Leave it to sit for an hour and then test again. If the alkalinity still isn’t high enough, simply repeat the process.

Once the water reaches the desired level of alkalinity, leave it overnight and come back the next day to test it again.

Test pH levels again

After you bring your alkalinity to the correct level, make sure you don’t forget to retest your pH level. This is because whenever you adjust the alkalinity of your tub, it will also probably alter the pH level of the water.

If you find that the pH level is out (the ideal reading for this is in the mid-7s on the pH scale), you will now need to adjust this.

There are several ways to change the pH level of your tub, and perhaps the easiest is to use a dedicated pH adjustment product – although the details of how to do that is a discussion for another day.

Always monitor your water for best results

If you own a hot tub, you need to monitor your water constantly, and testing it twice a week is recommended. This will allow you to discover any chemical imbalances quickly and take the necessary steps.

Adding Muriatic Acid To Pool Water

This will not only increase the hot tub’s life but also give you and your family a more pleasurable bathing experience.