Bleach vs pucks effective chlorine.......

[chem geek]

I did a cost comparison of chlorine sources in this thread. Basically, Trichlor at first appears to be less expensive per chlorine added until you account for the cost of the chemical needed to adjust the pH since Trichlor is very acidic. Obviously the costs are examples and you may find your costs to be somewhat different, especially for bleach and chlorinating liquid. The thing to keep in mind is that Dichlor and Trichlor will add to Cyanuric Acid (CYA) while Cal-Hypo will add to Calcium Hardness (CH).

The size of Trichlor pucks varies, but an 8-ounce puck in a 10,000 gallon pool will increase FC by 5.5 ppm and CYA by 3.3 ppm. It takes 14 cups of 6% bleach to get the same FC or 7 cups of 12.5% chlorinating liquid. It would take 11 ounces weight of Cal-Hypo 65% to get the same FC.