Dichlor is one of many types of chlorine used to sanitize your pool.
But, using dichlor will affect other aspects of pool chemistry. Let’s find out if it is the right choice your your pool.
What is Dichlor?
Dichlor, scientifically known as sodium dichloro-s-triazinetrione, is a fast-dissolving form of chlorine used to sanitize pool water. It is popular for pools and spas that need a quick dose of chlorine.
It’s known for its granular form, often called dichlor granular chlorine or dichlor shock. This makes it easy for pool owners to apply.
However, it can also be found as 1″ to 3″ tablets and can sometimes be confused for trichlor.
How is Dichlor Made?
Dichlor is stabilized, which means it contains cyanuric acid (CYA) and gives it a layer of protection from sunlight.
It contains about 55-63% active chlorine strength depending on which kind is used. It is also one of the only chlorine forms with a nearly neutral pH of 6.7.
It is produced in either anhydrous (with water) or dihydrate (without water). Most dichlor products you buy will likely be dihydrate.
How Does Dichlor Work And How Should It Be Used?
Dichlor dissolves and acts quickly in granular form. Upon application, it releases free chlorine (FC) into the water, which destroys harmful pathogens and bacteria, ensuring that the water remains safe and clean.
Using dichlor granules is relatively straightforward. It’s typically pre-dissolved in a bucket of water and scattered directly into the pool’s deep end.
Some owners use dichlor granules as a shock treatment. In this process, a large amount of the product is added to the pool to increase free chlorine levels.
If used in tablet form, they can be put directly into a chlorine feeder that floats in the pool and slowly dissolves into the water.
While similar, dichlor and trichlor should not be used together as the mixing of the two can result in toxic gases and even explosions. Both forms of chlorine should be used separately.
Use our pool chlorine calculator to know how much dichlor to add to your pool.
Should Dichlor Be Your Everyday Chlorine Choice?
Dichlor seems easy enough to use, and its fast-acting nature makes it an appealing choice for many pool owners.
However, it is also good to know some of the drawbacks of using dichlor and see if it is still the right choice.
Advantages of Dichlor
- As stated above, dichlor is fast-acting and fast-dissolving in granular form. That makes it super convenient for pool owners to use.
- Being pH neutral is a major plus so it won’t mess with the acidity or basicity of the water. Unlike trichlor, there is no need for pH adjustments after use.
- Having a higher chlorine strength of 55-63% means less of it has to be used to increase free chlorine levels.
- It has a very long shelf-life compared to other forms of chlorine. Rarely will it lose its overall strength over time.
Disadvantages of Dichlor
- It’s typically the most expensive type of chlorine to buy, especially when purchased in bulk.
- Being a stabilized form of chlorine means that each use will add CYA to the pool. Higher levels of CYA will force you to use more chlorine and the cycle will not end unless some water is drained (the only way to lower CYA levels is by draining and refilling with fresh water).
- Dichlor is highly volatile and can cause potential explosions if mixed with the wrong chemicals. While no chemical should ever be mixed together, this is especially important when handling and storing dichlor.
Should I Continue to Use Dichlor Granules As My Chlorine of Choice?
There is no denying the convenience factor when using dichlor for pools. The fact that they can be bought as tablets adds to the “set it and forget it” style of pool care.
However, the disadvantages outweigh the advantages of primary use. Dichlor is just too expensive to use daily. Also, the fact that it will increase CYA over time can add to the cost of needing to drain and refill the pool.
If CYA is a bit low, then dumping some granules in the pool is a great idea. Just ensure you are testing with each application so you don’t overuse it!