TriChlor - Further Reading

What is TriChlor

TriChlor is a chemical compound and the short name for trichloro-s-triazinetrione. Trichloroisocyanuric acid is another name.

TriChlor is essentially a combination of Cyanuric Acid (CYA) with chlorine. TriChlor also contains acid and will reduce the pH and TA.

Ratio of Chlorine and CYA

TriChlor releases a 2:1.2 ratio of FC to CYA.[1]

TriChlor is 10 ppm FC and 6 ppm CYA, no matter the brand. The only thing different is when they take a cheap chemical such as baking soda and put it with the triclor, so you get less FC and CYA with it for more money.

If you have 1000 gallons of water and add 1.5 ounces of TriChlor you will get 10 ppm FC and 6 ppm CYA. If you have 25,000 gallons of water and add 36 ounces of TriChlor you will get 10 ppm FC and 6 ppm CYA. If you have 500,000 gallons of water and add 46 lbs of TriChlor you will get 10 ppm FC and 6 ppm CYA.

The ratio never changes. 5:3

You may be told at pool stores that some TriChlor product has very low CYA, all TriChlor have the same ratio of chlorine to CYA. TriChlor is TriChlor. The molecule contains chlorine and CYA in the same proportions regardless of who puts it in the container.

Downside to TriChlor

The main downside to TriChlor, other than its acidity, is that it adds CYA to the pool and CYA is not something that breaks down (normally,) in pool water. So it continues to build up UNLESS you have significant splash-out, backwashing (if you have a sand filter or regularly clean your DE filter) or have lots of rain that overflows and dilutes your water. Otherwise, you would have to regularly drain and refill part of your pool water to keep the CYA level relatively constant.

When to Use TriChlor

  • Use TriChlor if your CYA is a little low and you want to increase it.
  • Use TriChlor when needing to leave the pool unattended and you can handle the CYA increase.

Usage Tips

  • TriChlor is very acidic so it should NOT be used in the skimmer and especially not if the pump ever stops running.[2]
  • Generally, if TriChlor is used, it is put into a floating dispenser which has it slowly dissolve. It can also used in an inline feeder.
  • Some manufacturers have started adding copper pucks/sticks/tabs to TriChlor. If the label says "Blue" that is a code word for containing copper. You do not want Copper in Pool Water.