Maintaining your pool water’s alkalinity at a certain range is important because it acts as a buffer to prevent sudden pH changes. The total alkalinity of your pool can be increased by adding baking soda (sodium bicarbonate), soda ash (sodium carbonate), or an alkalinity increaser.
A common question I hear is if there are any differences between alkalinity increasers and baking soda. Also, many first time pool owners struggle with maintaining their pool’s pH and alkalinity because they aren’t sure how much and what chemicals to add.
If you read your alkalinity increaser’s label, you’ll find that the active ingredient is 100% sodium bicarbonate. Sodium bicarbonate is baking soda, so yes, an alkalinity increaser is the same as baking soda. In other words, you could just as easily buy baking soda and add that to your pool with the same effect. The only difference is branding and specific instructions on the label with regards to how much to add. However, the active ingredient is exactly the same as regular baking soda.
In this article, we will discuss what you should know with regards to buying an alkalinity increaser instead of baking soda, common mistakes beginners make, and how to keep your pool water’s pH and alkalinity balanced.
Pool alkalinity increaser vs baking soda
First time pool owners often make the mistake of excitedly going to their local pool store, asking an employee for help, and then leaving with hundreds of dollars worth of chemicals the salesperson assures they need for their pool.
Now, maybe you do need some or all of those chemicals, but in the case of alkalinity increasers vs baking soda, there is literally no difference in the chemical that you’re using. You’re overpaying for something very basic just because it’s branded and comes with instructions.
It’s kind of like how you can buy name brand drugs like Advil or Tylenol or you could just buy their generic versions – ibuprofen or acetaminophen – often at significantly reduced cost and in greater volume.
Even if the local pool store slaps on a hefty discount for their alkalinity increaser products, enticing you into buying under the impression that you’re getting a good deal, chances are you could still get it for cheaper if you just bought baking soda in bulk.
How much baking soda should you add?
The recommended range for a swimming pool’s total alkalinity is between 80-120 ppm. You can determine this by using a pool testing kit to learn the range of your pool water so you know how much you need to increase the alkalinity by.
The rule of thumb is to add 1.5 pounds of baking soda into a 10,000 gallon pool to increase the alkalinity by 10 ppm. So if you have a 30,000 gallon pool, adding 4.5 pounds of baking soda will increase the alkalinity by 10 ppm.
You can quickly see how you would need an enormous amount of baking soda, which is why it’s highly recommended to buy it in bulk and to avoid name brand alkalinity increasers to save a lot of money in the long run.
If you’re not a fan of doing calculations, you can literally just use a pool calculator to do the math for you.
It’s important to test your pool water often, since keeping the pH and alkalinity in the optimal range can solve many problems and prevent a lot of headaches.
Does alkalinity increaser only increase alkalinity?
Another common mistake beginner pool owners make is assuming that a product known as an “alkalinity increaser” doesn’t just increase alkalinity, but the pH as well. The reason for that is because it’s literally just baking soda, and baking soda can increase both pH and alkalinity.
With that said, baking soda and alkalinity increasers both most increase the alkalinity while keeping the pH increases to a minimum.
You should also be very careful that you don’t accidentally add a product where the primary ingredient is sodium carbonate. Sodium carbonate is soda ash, which is much more potent than baking soda.
Yes, soda ash can substantially increase the pool’s alkalinity and pH, whereas baking soda mostly increases the alkalinity and the pH only slightly.
Use a water testing kit to carefully monitor the pH and alkalinity to ensure that both are in the optimal range.
How do I know if the alkalinity is too high?
Aside from using a water testing kit, there are many ways you can tell when the alkalinity is too high. Since there is a close relationship between pH and alkalinity, the side effects are similar to when the pH is too high.
When the alkalinity is too high, the chlorine will become ineffective and lead to an increase in germicidal activity. The water can also become cloudy, reducing visibility and overall safety in the pool.
You may notice calcium buildup, resulting in scaling, clogged filters, and stains on the pool liner. Since alkalinity acts as a buffer for pH, you will find it difficult to adjust the pH if the alkalinity is too high.
Again, keep in mind the optimal range for the pH and alkalinity of the pool is 7.4-7.6 and 80-120 ppm respectively. Use a water testing kit often to ensure it stays within this range, and that you have not accidentally added too much baking soda or soda ash when balancing your pool chemistry.
The bottom line
If your alkalinity increaser is just 100% sodium bicarbonate, then it is the same as using baking soda. There is no comparison to be had because they are the same thing.
You’ll notice alkalinity increasers are more expensive – i.e. it costs more to buy a smaller amount compared to buying baking soda in bulk – and that’s essentially because you’re paying for the brand name. Don’t fall for any “discounts” either; it will likely still be more economical to buy baking soda at regular price in bulk.
Be very careful when buying baking soda, as it is often labeled as sodium bicarbonate which is very similar sounding to sodium carbonate, which is not the same thing. Sodium carbonate is also known as soda ash, which has a much higher pH value and will drastically increase both the pH and alkalinity when added into the pool.
Don’t make the mistake in thinking that an alkalinity increaser only increases the alkalinity. Since it is essentially baking soda, which has a pH of 8.3-8.6, it can also increase the pH in addition to the alkalinity. You need to ensure that you aren’t accidentally increasing the pH too much and to adjust as needed. This can be done by frequently measuring the pool using a water testing kit and adding chemicals as needed to ensure the water is in the optimal pH and alkalinity range.