How Much Muriatic Acid To Lower Alkalinity In Hot Tub

How To Raise pH in Hot Tub

Like any other major purchase, if you have decided to invest in a hot tub you will want to know how to properly maintain it in order to extend its lifespan. You’ll need to keep the water balanced to gain benefit from owning your own hot tub so your and friends can use it safely.

There is a short list of chemicals that you will need to keep on hand to keep the water maintained and the pH and alkalinity levels balanced.

The chemicals used to balance pH and alkalinity are inexpensive but are extremely important. Water pH is a measurement of the acidity of your water.

The human stomach naturally produces muriatic acid to increase the pH level in the gut. This will eliminate microorganisms that cause you to get sick and assist with the digestion process. In a swimming pool, the muriatic acid can reduce the pH and alkalinity levels in order to balance the chemistry of the water.

Just to give you an idea why this is, our skin acidity is 7.35 to 7.45, so this lies in the middle of the suggested water acidity range – that way we are more comfortable in our spa and at this range bugs are kept under control more easily.

If your pH fluctuates outside that safe zone, the water becomes unsafe and can cause corrosion, mineral scaling, or you can face unhealthy bacterial growth.

Alkalinity is a measure of the water’s ability to buffer the pH to neutralize the acid.

It may seem complicated at first, but with a little practice it becomes routine.

To calculate how much hydrochloric acid (muriatic acid) your swimming pool requires to decrease the total alkalinity, choose the reduction you want and enter the volume of your swimming pool. Desired reduction in total alkalinity 10 ppm 20 ppm 30 ppm 40 ppm 50 ppm 60 ppm 70 ppm 80 ppm 90 ppm 100 ppm. In order to lower both the pH and alkalinity of your hot tub water, you will need to add acid. Common choices are liquid muriatic acid or dry sodium bisulfate. When the acid is introduced to the water, it increases the hydrogen concentration and lowers the pH.

It helps keep pH levels stable so when your water dips out of range, you can simply adjust your TA (Total Alkalinity) without having to completely redo your hot tub chemistry.

Alkalinity should be between 125ppm and 150ppm and be adjusted first since it keeps your pH in check, so when it slips levels, your pH will as well.

  • 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.
  • When determining the amount of muriatic acid to use, you would first want to know the pH and alkalinity levels, along how many gallons of water does your hot tub usually holds. Once, you have that information the detailed labeling on the muriatic acid should point you in the right direction of exactly how much to add.

Failure to maintain alkalinity may result in corrosion, phosphate imbalance which can lead to algae growth and green water, mineral build-up, and cloudy water.

On top of these effects, there’s every chance you will be developing bacteria-rich water by allowing bacteria from either side of neutral to breed to excess.

What causes low pH in hot tub?

Testing kits for pH levels are available at pool supply stores. You dip a strip into the water and read the pH by matching the color it turns to a scale printed on the bottle. The ideal level should be in the neutral range.

The one in the picture shown runs at just over the $10 mark directly from Amazon, so there’s no great cost involved with these tests.

You will also need some test strips to take a sample of your water – again, inexpensive.

An alternative to the test strips is to use a digital meter costing almost double but this one does not need the strips, so will soon pay for itself.

Elevated levels of acid cause sanitizing chemicals to become ineffective allowing harmful contaminants to come in contact with bathers, which can lead to rashes and eczema.

It can also irritate swimmer’s skin and eyes. Too much acid takes its toll on your tub’s components causing them to corrode.

So, what causes low pH in hot tub spas making the water excessively acidic?

In a word, if you’ve set the chemical levels right to start with, it’s YOU – and anyone who joins you in the hot tub.

It is well known we all sweat in hot tubs, and it is these bodily fluids, along with flaky skin, anything that is or was living, rots down and causes acidity. So the more people you have in there and for a longer time without water changes, then your water will grow more and more acidic as time passes.

On top of that pH that’s too low can be caused by the type of water you use.

Soft water will have a completely different pH than hard water. Thus, when you add water, it will alter your level accordingly.

Different chemicals you use will also cause fluctuations since they have different pH ranges too. When the time comes to add more chemicals, the levels will change depending on the amount used and the pH level of that specific chemical.

How to raise pH in hot tub

Low levels can cause skin irritation and degrade the spa’s heater and other components. The pH levels in your hot tub can be increased by using magnesium oxide which has the ability to neutralize carbon dioxide.

The first step is to adjust the alkalinity using either of the test methods above.

The next step you take in how to raise pH in hot tub spas is you gradually add an increaser like SpaGuard pH Increaserto get the right reading.

Then allow the tub to run for 30 minutes to evenly circulate the chemicals.

Last, turn off the jets and conduct a retest to ensure the alkalinity is still at proper levels.

What causes high pH in hot tub?

A high pH level is a level above 7.6 ppm. This means your water is too basic, too alkaline, and when your water pH is too high, it can begin to form scales.

Scales are a white and chalky residue that’s rough to the touch and can be found on the tub’s surfaces.

These scales can block water circulation by becoming lodged in pipes and blocking their flow. As they build, scales will cause early equipment failure.

These scales are formed by the Alkaline effect forming lime which eventually will become like chalk in that it will block your pump and piping if left for too long without balancing the water.

On top of this, you may notice a greeny tinge developing in your water which, if left too longe, will eventually form algae.

You will need to regularly use a pH reducer and we recommend Leisure Time Spa Reducer.

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

Reducers usually consist of dry acid crystals such as sodium bisulfate but liquid forms are also readily available.

The pH reducer needs to be added gradually over a period of time depending on the manufacturer’s recommendation. You add it gradually, allow it to circulate, and then retest the pH level. If it is still too high, you repeat the process until it gets in range. Adding too much reducer too quickly can result in making the water too acidic that you will have to get to come back down.

The most common reason for an elevated pH level is a very high alkalinity level. Since alkalinity acts as a buffer to help keep pH in range, when it raises, so will your pH level because it will not be able to keep it under control.

Hot tubs run at a higher temperature and produce bubbles which cause a buildup of carbon dioxide. The carbon dioxide is also notorious for raising both pH and alkalinity. As has been stated, this carbon dioxide is also a result of living matter decomposing.

How much muriatic acid in pool

How much muriatic acid to lower pH in hot tub?

Muriatic acid(also called hydrochloric acid) is another chemical commonly used to lower a spa pH level that is too high. The amount you use will depend on the capacity of your hot tub and how high the pH actually is.

How much muriatic acid to lower pH in hot tub spas? Here is a general amounts guide:

• 400 gal. spa:
o 7.6-7.8: .5 fl oz.
o 7.8-8: .6 fl oz.
o 8-8.4: 1 fl oz.
o Above 8.4: 1.3 fl oz.

How Much Muriatic Acid To Lower Ph

• 750 gal. spa:
o 7.6-7.8: .9 fl oz.
o 7.8-8: 1.2 fl oz.
o 8-8.4: 1.9 fl oz.
o Above 8.4: 2.4 fl oz

• 1500 gal. spa:
o 7.6-7.8: 1.9 fl oz.
o 7.8-8: 2.4 fl oz.
o 8-8.4: 3.6 fl oz.
o Above 8.4: 4.8 fl oz

How to lower pH in hot tub home remedy?

Many people have issues where the spa chemicals can irritate their skin or cause health problems. Others may just want a more natural alternative.

Adding Muriatic Acid To Pool Water

That leaves many questioning how to lower pH in hot tub home remedy?

Here are a few alternative methods to lower pH levels without harsh substances.

• Lemon juice or vinegar both contain acids that can bring pH levels down. You will have to use plenty of it because vinegar only contains about 5 percent acid.
Using peat moss is generally thought of as the most effective natural method of dropping pH. Peat moss can be placed in a mesh bag and placed somewhere the water will flow through it.
• Driftwood acts as a natural filter. It will need to be soaked for a few days prior otherwise it will discolor water.
Use distilled water
• Install a carbon dioxide system to monitor and adjust pH levels automatically

Another alternative to using chemicals is to use baking soda to reduce the acidity of your water – check out our post on How Much Baking Soda to Raise Alkalinity in Hot Tub

Again – if you are not into chemicals, then I suggest you take a look at our post Running Hot Tub Without Chemicals

Keeping your hot tub water in at a neutral pH level is important both for the longevity of your spa, as well as for the people who use it.

Alkalinity and pH go hand-in-hand and work together to keep your water safe. Without regular chemical maintenance and testing, you will experience issues like bacterial growth, algae, scaling, eye and skin irritation, and corrosion.

Muriatic Acid To Lower Your Pool Alkalinity - Pool & Hot Tub ...

So make sure you know how to raise or lower pH in your hot tub for your own benefit and your hot tub’s.

On the other hand, if you are like me, lazee, and want an easier option, how about the pHin Wi-Fi-Enabled Smart Water Care Monitor for Hot Tubs and Pools.

Once set up, just drop it in your pool water and it will let you know as any problems arise and literally tells you, directly to your phone, what needs doing to correct the problems.

Not cheap, but well worth the loss of aggravation.

There are even videos showing how to set it up and how it works here.

We use one ourselves and can highly recommend them.

With 135 positive customer reviews so far. – It’s a Godsend to us!

Why not check out some of our other informative posts:

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