I don't feel as if I'm violating OPSEC in this post, so here goes:
After I lost my job as a research scientist due to budget cuts at the DoD, I switched industries and began working as a building engineer at a large chain in the hospitality industry. If I posted name of my employer, doubtless many would recognize it, but I'll keep that to myself.
I do believe working in the hospitality industry in the Central Florida area is a pretty big group of folks, so I don't think that's giving too much away.
One side effect is my facility has a 62,000 gallon pool somewhere in Central Florida, and I'm responsible for it as well as other parts of the facility. My employer was kind enough to pay for my Certified Pool Operator's license, so I know a bit about pool chemistry.
My employer purchases granular Calcium Hypochlorite in 100lb containers for each facility with pools. Cal Hypo is a great shelf stable oxidizer and sanitizer, the two are not the same. I use it primarily for shocking the pool to remove cloudiness and excess chloramine (combined chlorine). We also get a form of cal hypo pucks for our auto feeders.
Now one nice thing about cal hypo is the hypochlorite ion does exactly the same job as sodium hypochlorite, only you get two ions per mole with cal hypo as opposed to one per sodium hypo. More bang per ounce, shelf stable, granular, highly concentrated and fairly easy to handle. It is MY go-to chemical for water disinfection. It also can be used to make a household bleach solution.
Generally I mix up a 500ppm (5%) solution with water to equate to a bottle of commercial bleach, approx 1 tablespoon to one gallon water. Then I follow the usual directions about disinfection.
One word of warning DO NOT UNDER ANY CIRCUMSTANCES ALLOW THIS CHEMICAL TO MIX WITH ACID (or any solution with a pH<6) . The result will be free chlorine gas, the stuff that killed soldiers in WWI. You will die a horrible death within minutes from pulmonary edema. But since the water supply you will be working with usually has a pH of 7-8, this is not a problem.
Now a word about trichlor, AKA cyanuric acid. CYA is a stabilizer used by outdoor pools to prevent UV light from the sun prematurely breaking down the sanitizer. CYA can be used to sanitize water, and actually is more potent than Cal hypo, but I find it to release chlorine much slower, and requiring a longer contact time to be effective. It is a backup plan to be sure, but I'll reach for the cal hypo first. I don't have the charts in front of me, just working from memory.