Swimming Pool

A pool's filter system does the heavy lifting in keeping the water clean, but it takes chemistry to do the fine-tuning. It's important to carefully manipulate the chemical balance in pools for several reasons:

Dangerous pathogens, such as bacteria, thrive in water. A pool filled with untreated water would be a perfect place for disease-carrying microorganisms to move from one person to another.

Water with the wrong chemical balance can damage the various parts of the pool.

Improperly balanced water can irritate the skin and eyes.

Improperly balanced water can get very cloudy.

Below are some of the main pool chemicals divided into helpful sections based on their function.

1. Sanitizers

Sanitizers are some of the most important chemicals you can use in your pool. They're absolutely essential, as they're the main ingredient that keeps your pool water clean and safe. Sanitizers stop health risks like bacteria, viruses, algae, and other unwanted pollutants from having free rein over your pool's water. They're critical in keeping your pool water looking good, too.

Chlorine

Chlorine is the most common type of pool sanitizer. As an oxidizer, chlorine enters the water contaminants molecules and destroys them from the inside. Chlorine is an excellent choice for removing bacteria, viruses, and algae, and it can even prevent algae from appearing to begin with. The Centers for Disease Control and Prevention (CDC) recommends a free chlorine content of 1 part per million (ppm) in your pool water.

There are two main types of chlorine to choose from:

• Stabilized chlorine: Stabilized chlorine contains cyanuric acid. The sun's rays decompose the active chlorine in your pool, rendering it ineffective. The cyanuric acid protects the chlorine, allowing it to stay effective longer, even with the sun beating down on it all day long. This means you'll save money by avoiding having to add more chlorine as often. Note that too much cyanuric acid in your water can make the chlorine less effective, so you have to strike the right balance.
• Unstabilized chlorine: Unstabilized chlorine lacks cyanuric acid, making it less effective at cleaning your water after extended exposure to sunlight. This also means unstabilized chlorine will avoid the potential downfall of decreased potency that cyanuric acid brings. If you have an indoor pool, unstabilized chlorine could be a great option for enjoying the benefits of chlorine without the concerns of added cyanuric acid.

You can also add cyanuric acid yourself for more control over your pool's chemistry. Be sure to read the information on your stabilized chlorine or cyanuric product packaging to avoid accidentally raising the pool water's cyanuric acid levels too high.

Bromine

Bromine may be the most popular chlorine alternative for pool sanitization. It sanitizes through ionization, breaking apart the molecular bonds of pool water contaminants. According to the CDC, the bromine level should be 3 ppm if you use it as pool sanitizer.

Some people prefer bromine over chlorine because it has a longer active life after you add it to the water. After adding bromine to your pool, it sanitizes the water without the need for added bromine longer than chlorine would sanitize before needing more chlorine.

Most bromine products contain small amounts of chlorine for added sanitizing power.

Biguanide

The pool chemical biguanide originally started as a surgical disinfectant similar to hydrogen peroxide. It's chlorine-free, which may be a positive for people sensitive to chlorine and its byproducts. It's also more expensive than chlorine and bromine.

Biguanide works by forcing small contaminants together into larger clumps that resist dissolving into the water. After clumping, the contaminants are a better size for your pool's filter to grab and remove them from the water. Unfortunately, this can contribute to more frequent filter clogs.

2. pH

A substance's pH level is a measure of its acidity or basicness. Measuring your pool water's pH is essential for having the best experience possible while making caring for your pool easier over time.

The pH scale ranges from 0 to 14, with 7 being neutral. Anything below 7 is acidic, and anything above 7 is basic. The CDC recommends a pH level of 7.2 to 7.8 for residential pools.

If you need to increase or decrease your pool's pH level, the answer is simple — use a pH increaser or a pH decreaser. These products will help you achieve the ideal pH level for your pool for safe, clean swimming.

Dialing in the right pH for your pool water might take some trial and error, and you may have to start slow. With dedication and commitment, you can reach that ideal pH range for your pool.

3. Alkalinity

Alkalinity refers to your pool water's ability to resist sudden spikes or dips in its pH level. In other words, alkalinity is like a buffer for your pool water, keeping it more stable and balanced throughout pool season regardless of what the summer throws at it. The CDC recommends an alkalinity of 80 to 120 ppm in pool water for the best results.

To get the best alkalinity level for your pool, you have two main product options:

• Baking soda: Baking soda is a common chemical you can buy from the nearby grocery store, but you can also get large quantities of it from specialty pool stores. Pour it into your water little by little and test the alkalinity to see the results.
• Alkalinity increaser: You can also buy alkalinity increaser if your pool water's alkalinity is too low. Alkalinity increaser also increases pool water's pH. There aren't any alkalinity decreasing products on the market, but pH decreaser will also decrease your pool's alkalinity if need be.

When adjusting alkalinity, it's important to start slow and take many chemical measurements to avoid overcompensating. If alkalinity is too high, try adding pH decreaser to lower both the pH and alkalinity. Add pH increaser to get the pH back to its ideal spot after hitting the right alkalinity. It's definitely going to be a balancing act that will take time and practice to get right.

4. Calcium Hardness

Calcium hardness is the measure of how soft or hard your pool water is. Where you live and where you get your water greatly impact the pool's calcium hardness. For instance, well water is often hard, which means it has a high concentration of minerals, including calcium. If you use that same well water to fill your pool, you'll be dealing with pool water with a high level of calcium hardness.

The CDC recommends a calcium hardness level between 200 and 400 ppm. Maintaining this range is crucial, as dipping below 200 or above 400 can have consequences you want to avoid.

If your pool's calcium hardness is too low, water may begin leeching minerals from your pool surfaces, which contributes to corrosion. If your pool's calcium hardness is too high, your water can turn cloudy and start dumping the excess minerals on your pool surfaces. This leads to a white film on pool surfaces, known as scale.

Achieving the recommended calcium hardness range gives you the best chance of avoiding these unwanted outcomes. Use a calcium hardness increaser if your level is too low, or remove some water and add soft water to your pool if your calcium hardness is too high.