Are Trichlor pucks 6ppm of cya?

borjis

LifeTime Supporter
Aug 19, 2014
3,612
Pacific NW
My pool was down to 35 ppm cya. good.

But I wanted it to be closer to 45-50 max (pool gets full sun every day) so that it would use a little less chlorine each day.

I put 3 leftover trichlor tabs in and they dissolved in a week.

Then I put 4 more in and dissolved.

I tested CYA recently and now its 80ppm.

For a 23,000 gallon pool are the trichlor pucks 6ppm cya each? sure seems like it.

I guess I should have tested after the first 3.
 
I'd recheck the test results.

Effects of Adding Chemicals at the bottom of poolmath indicates that for a 23000 gallon pool, 7 8oz pucks - 56 ounces - of trichlor should only add 10 CYA. Either you were higher than you thought before or you're lower than you think now or those are some awful big pucks.
 
That's about right. Depending on the type of puck, one puck can add anywhere from 6-9 ppm. It adds-up fast. Yikes.

Not really. The following are chemical facts that are independent of concentration of product or of pool size.

For every 10 ppm Free Chlorine (FC) added by Trichlor, it also increases Cyanuric Acid (CYA) by 6 ppm.
For every 10 ppm FC added by Dichlor, it also increases CYA by 9 ppm.
For every 10 ppm FC added by Cal-Hypo, it also increases Calcium Hardness (CH) by at least 7 ppm.

Usually "pucks/tabs" are Trichlor. Sometimes one can find Cal-Hypo pucks. Very rarely Dichlor as fast-dissolving small tablets for spas.

A single puck does NOT add 6 ppm CYA to most pools. One 3" 8-ounce Trichlor puck in 10,000 gallons adds 5.5 ppm FC and 3.3 ppm CYA. It adds less in larger pools, more in smaller pools (because the ppm is a concentration so is lower in larger volumes of water).

The amount of CYA in Trichlor and Dichlor is a FIXED amount because it is part of the chemical itself. It is not added separately. Three chlorine atoms are bound to CYA in Trichlor while two are bound to CYA in Dichlor.
 
Thread Status
Hello , This thread has been inactive for over 60 days. New postings here are unlikely to be seen or responded to by other members. For better visibility, consider Starting A New Thread.