Being a pool owner can sometimes feel like being a chemist. You have to mix many chemicals with your pool water and closely monitor the pH and alkalinity so that the water chemistry is balanced. If you mess up, your pool water can turn green, red, or brown – colors that make you never want to swim in the pool again.
To ensure this doesn’t happen, you want to keep your pH between the range of 7.4-7.6 and the alkalinity around 80-120 ppm. Too much or too low and the sanitizing chemicals you add, such as chlorine, won’t be as effective.
Since pools tend to become more acidic over time, you need to increase its pH and alkalinity to maintain it within the safe range, and an easy way to do that is to add baking soda into your pool. The issue is that sometimes you need to add a lot of baking soda or soda ash, and if you’re not careful, you can add too much baking soda into the pool.
When you add too much baking soda or soda ash and raise the pH and alkalinity too high, it can render the chlorine ineffective. It can also lead to calcium buildup in your pool, cloudy water, clogged pool filters, and irritated skin. You can decrease the pH and alkalinity by adding muratic acid or using a pH decreaser to balance the pH.
In this article, we will discuss the consequences of adding too much baking soda into the pool, how much you should add, and how to decrease the pH and alkalinity with muratic acid in case you added too much baking soda in the first place.
What happens if the pool water is too alkaline?
As mentioned, the sweet spot for pools is a pH of between 7.4 to 7.6. If the alkalinity increases and bumps the pH above 7.6, then the following can occur:
- You can experience itchy and irritated skin.
- The water becomes cloudy, reducing visibility.
- Chlorine becomes ineffective, resulting in greater germicidal activity.
- Calcium can build up, causing an increase in scaling and clogged pool filters.
When this happens, pool owners should add an acidic substance to balance the pH within the 7.4 to 7.6 range. This requires some fine-tuning, because you can accidentally add too much acid into the pool, requiring you to add more baking soda again.
Should you add baking soda or soda ash?
A common mistake newbie pool owners make is not differentiating between baking soda (sodium bicarbonate), soda ash (sodium carbonate) and alkalinity increaser, as well as not knowing how each affect pool pH and alkalinity.. They both can raise the overall pH and alkalinity of the pool water, but they excel in different areas.
For example, baking soda can increase the alkalinity greatly without affecting the pH very much. Soda ash, on the other hand, can increase both the pH and alkalinity of the pool water substantially.
Therefore, if your pool has low pH, the optimal choice is to add soda ash so that it can increase the pH with much less chemicals required. If you chose to add baking soda, you may increase the alkalinity too much before the optimal pH is met.
On the other hand, if the pH is near the optimal range but the alkalinity is low, then you should be adding baking soda instead so as not to increase the pH too much.
How much baking soda or soda ash should you add?
Get ready to buy baking soda in bulk, because you’re going to need a lot. A good rule of thumb is to add 1.5 pounds of baking soda for every 10,000 gallons of water in your pool.
For perspective, even a small above-ground pool holds 13,000 gallons of water on average. Larger pools may require you to add several pounds of baking soda, and you’ll have to do this weekly.
There are a few ways to add baking soda to your pool. You can just add it directly into the pool by sprinkling it in wide arcs so that it’s not all concentrated in one place.
Or you can mix it in water first in a bucket until it forms a thin paste. This allows you to smooth out any clumps before you dump it into the pool, helping it mix more easily.
Make sure to leave the pool pump running to help disperse the baking soda more evenly. A trick you can do is to pour the baking soda near the return jets to help it spread faster.
To be safe, wait at least six hours for the baking soda to fully dissolve and mix into your pool. Do not be hasty and add more baking soda too quickly, as this can quickly lead to adding too much baking soda into the pool.
After waiting the elapsed time, if the numbers are still too low, then add more baking soda. It is better to add conservative amounts at first and then add a bit more later on if needed so as to avoid adverse side effects with adding too much.
- Industrial Grade Soda ash (Sodium Carbonate) Na2CO3 99.8+% Soda Ash, 0.2% Water
- May be used for water softening, making glass, regulating pH levels
- Excellent base for cleaning up chemical spills, oil absorbant
Soda ash requires more care than baking soda. Grab your goggles and gloves, because direct contact can harm you due to its significantly higher pH level.
Once you’ve worn your safety equipment, fill a bucket with pool water and add the desired amount of soda ash. You need six ounces of soda ash for every 10,000 gallons of water.
Use a stick or other object to stir the soda ash in the bucket until it dissolves into the water. Then pour this solution into the pool. It’s best to pour near the return jets to help it disperse faster.
Just like with baking soda, you should wait at least six hours before testing your pool’s pH and alkalinity levels. Again, we recommend being conservative and slowly adding more as needed so you don’t add too much.
What if you added too much baking soda or soda ash?
- Lowers high pH in swimming pool water
- Restores neutral pH
- Protects from scale
If you’ve accidentally added too much baking soda or soda ash and increased the pH and alkalinity too much, you can either buy a pH decreaser or use muriatic acid to lower them to the optimal levels.
Muriatic acid, also known as hydrochlorous acid, is the cheaper option. pH decreasers come in powder form, are milder than muriatic acid, and are ultimately safer to use but more expensive. Besides, you may already have muriatic acid on hand because it’s often used to clean pool filters and surfaces.
Since muriatic acid is an acid, you need to wear the proper safety gear. It can burn your skin in seconds, and inhaling the vapors can cause respiratory issues.
To keep yourself safe, you need the following:
- Acid-resistant gloves.
- Safety goggles.
- Chemical-resistant apron.
- A vapor mask.
- A bucket.
- A wooden or plastic stirrer.
And of course, you need pool-grade muriatic acid. Since it is hazardous, it can be harder to order online, but local pool stores should have them in stock. Once you’ve got everything prepared, it’s time to fix your pool water.
- Test your pool water. Knowing your pool’s pH and alkalinity will help you determine how much muriatic acid you need to add to bring them to the optimal range. Use a test strip or a digital test kit to find out this information.
- Calculate how much muriatic acid to add. Read the label on your muriatic acid to determine how much acid to add. You can also use an online calculator to help with this. A rule of thumb to follow is that adding 20 ounces of acid in a 10,000 gallon pool will lower the alkalinity by 10 ppm. If the pH levels drop too low after the optimal alkalinity is reached, set your pump to aerate to bring your pH levels up.
- Set your pump to circulate. Before adding the acid, set your pump to circulate to help disperse the solution as soon as you add it. Turn off any water features such as fountains or aerators in the meantime.
- Add the muriatic acid. You can add muriatic acid directly to the pool, but a safer option is to mix it in an acid-resistant bucket first. The ideal ratio of water to acid is 10:1, but defer to the manufacturer’s instructions. Add water first, then the acid; adding acid first runs the risk of splash back. If adding directly to the pool, add it from the deep end first, and walk as you pour so you don’t inhale the fumes.
- Wait patiently. Let the pump circulate the acid for 30 minutes. This keeps the acid from settling and damaging your pool surfaces, especially the floor. Afterwards you can turn the pump off, but you should still wait a few hours for the acid to fully dissolve and mix into the pool before taking any other actions.
- Retest your pool water. Use another test strip to see if your pool’s pH and alkalinity is now in the optimal range of 7.4-7.6 and 80-120 ppm. If it hasn’t gone down enough, keep adding muratic acid in doses of half a gallon or less. If you accidentally go too far in the other direction, then it’s back to adding baking soda/soda ash to make the pool more alkaline.
Note: The product featured in the image at the top of this article claims to be a 1-to-1 replacement for muriatic acid, with 90% reduction in fumes, no risk of burning skin, and the same cleaning, etching, and pH reduction properties as muriatic acid. Reviews back these claims up, so I’d say give it a shot. You can follow the same steps, but this will make the process much safer. Check out the product below.
- Item Weight: 1.0 lb
- Country of Origin: United States
- Brand name: CERTOL INTERNATIONAL
The bottom line
Regardless if you’re adding baking soda, soda ash, or muriatic acid, make sure you are doing it in conservative quantities so that you don’t go overboard. The water chemistry must be kept in a delicate balance, otherwise it will be unsafe to swim in. Whether it’s too alkaline or too acidic, these are both undesirable situations that you need to address by either adding baking soda or muriatic acid until the pH and alkalinity are in the optimal range.
Last update on 2023-05-14 / Affiliate links / Images from Amazon Product Advertising API