Different Types of Pool Chlorine Sanitizers

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Chlorine is the most popular chemical used to sanitize pool water. It helps keep the water clean, fresh, and away from algae and other microorganisms. Simply put, the chemical is the first line of defense against viruses and germs in the swimming pool water. 

However, selecting the suitable sanitizer for your pool depends on your affordability, benefits, and personal preferences. Chlorine sanitizers come in liquid, tablet, and powder forms, with a few crucial differences. This article will walk you through various chlorine sanitizers and how they effectively sanitize the pool water. 

Accordingly, we hope to help you make the right choice when choosing a pool chlorine sanitizer and have a safe and healthy time in the pool. Let’s start!

Chlorine Gas

Chlorine in the gaseous form is the most potent type of chemical as it is 100% pure. Most pool maintenance professionals and public pools use chlorine gas to disinfect pools, as the gas raises the pool’s chlorine levels more efficiently than the liquid acidic form. As compared to the other chlorine types, gaseous chlorine is highly cost-effective. 

However, the major drawback of using chlorine gas is that one needs to be extremely careful using it, as it can be hazardous. For this reason, the use of chlorine gas for residential purposes is decreasing day by day. 

The gas is also highly acidic, thus requiring a high base to balance the pH levels of the water. Therefore, the use of sanitizing gas has become very rare, as it has been banned in many countries.

Chlorine Tablets (Trichlor)

One of the most typical forms of chlorine sanitizers is chlorine tablets. They are mainly used for residential and private pools of all sizes. The significant benefit of using chlorine tablets is that they are cost-effective, readily available, and require less time for dispersing throughout the pool water.

The chlorine tablets are also known as trichlor, as they consist of 90% chlorine, being highly efficient in pool sanitizing. However, while using chlorine tablets, remember to use some extra-base to maintain the water’s pH to 7.2 or 7.3 because the pH of the tablets is relatively low. 

You must also ensure to disperse the tablets evenly throughout the pool’s water; therefore, tossing them directly into your pool is not something we would recommend. Instead, using an automatic chlorinator is advised for dispersing chlorine tablets.

Sodium Hypochlorite (Liquid Bleach)

Sodium hypochlorite is another standard chlorine pool sanitizer generally used among pool maintenance professionals. It is also known as liquid bleach, which is highly beneficial and the least costly among chlorine pool sanitizers. As the most common and least expensive pool sanitizer, most large commercial pools use this type of chlorine sanitizer as they need to pour it in bulk inside the bigger pools. 

The quantity of chlorine present in the liquid bleach is 10-15%, with a pH value higher than 13. Therefore, when using sodium hypochlorite, you will require more acid to balance the pH levels. Another major drawback with liquid bleach is that it is highly corrosive to the pool’s floor and can have a few disadvantages in the longer term. 

Therefore, the liquid bleach is not recommended for residential use due to its corrosive properties, limited availability, and hazardous nature.

Calcium Hypochlorite 

Calcium hypochlorite is one of the most readily available granular chlorine sanitizers. The amount of chlorine present in this powdered form is around 65-73%, combined with a few other chemicals like calcium carbonate and calcium chloride. Therefore, it is more cost-effective than other liquid pool sanitizers due to the amount of chlorine present. 

However, the pH level of calcium hypochlorite is higher up to 12. Thus it would need added acid to maintain the pH levels. Another con of powdered chlorine is that it can make the pool water harder, which can cause corrosion to the swimming pool’s surface if it stays hard for too long. 

The water with calcium hypochlorite quickly becomes very dusty and contaminated, causing combustion because of higher volatility.

Dichlor (Sodium Dichloroisocyanurate)

Hands down, one of the best chlorine sanitizers used worldwide is sodium dichlor. Like calcium hypochlorite, the chlorine concentration in dichlor is also around 65%. The best pros about dichlor sanitizers are that they dissolve in the water in real-time and effectively act upon contamination. It comes in powder forms, making it more convenient to disperse in the water than chlorine tablets.

However, one of the most considerable drawbacks of using sodium dichloroisocyanurate is that it increases the levels of cyanurate in the water. There is also a chance of catching fire when using dichlor, and the chemical is relatively more costly than other powdered chlorine forms, depending on the available chlorine.

Dichlor is a lot more costly than cal-hypochlorite. 

Lithium Hypochlorite

Another type of powdered chlorine sanitizer, lithium hypochlorite, consists of only 35% of chlorine, making it a weak solution comparatively. Like Dichlor, lithium hypochlorite is quite expensive because of the high demand for the chemical in other industries, particularly batteries. For instance, if 1 lb of calcium hypochlorite costs $10, the same amount of lithium hypochlorite will cost $50. 

Because of the high cost, the chlorine sanitizer is not commonly used for commercial or residential purposes. However, one significant benefit of lithium hypochlorite is that it quickly disperses in the water, thus reducing any risks of corrosion to vinyl pool surfaces.

Wrapping Up

While we learned the significant pros and cons of each type of pool chlorine sanitizer, it is also essential to know that chlorine that dissolves and reacts slowly is the most suitable for daily sanitization of a swimming pool. Therefore, we recommend chlorine tablets for small and large pools, consisting of the qualities mentioned. 

The tablets are readily available and are convenient to use and store. For larger pools, liquid chlorine is suitable, and powdered chlorine sanitizer will best work for rapid dissolving.

Therefore, according to your preferences and budget, there are many options for chlorine sanitizers. 

However, you must remember that lithium hypochlorite and chlorine gas are hardly available anymore due to their cost and hazardous nature. Hence, we recommend choosing from the commonly known types like dichlor, liquid, and calcium hypochlorites. Good luck! 

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