How do you regulate chlorine if you don't have something like a Frog?
There is no regulation of chlorine. The UV from the sun burns off 2 to 4 ppm a day across the season, with less in the early/late season, and more in the peak season.
Period.
Unless you get rid of the sun, you will have to replenish the FC burned off by it.
Period.
Any system that claims you will need less chlorine is spinning a bold faced lie. The irony with UV systems is that they burn off some FC also, ensuring you need MORE chlorone than you would have, while also touting that you'll need less. (The residential UV units are risky dink and consume much less than the sun, but technically it's still regulat UV loss, plus more UV loss from the device)
All these systems, and the industry in general for that matter, are fixated on algae control. They bark up the wrong tree because in a balanced and sanitary pool, there's no algae to deplete your FC. If your pool is unsanitary with active algae blooms going on, then yes, the systems will likely kill some algae, needing less chlorine to do so, but that still doesn't alter the 2 to 4 ppm lost to the sun. So instead of 4 + 4, maybe you need 4 + 2. Their claims you only need 1 or 2 ppm total per day because their of system are again entirely ignorant and/or bold faced lies.
One can make up their own mind whether the industry method creates many problems to solve with expensive cures on purpose for financial gain, or if their method does so and they are ignorant to the root of the problem and helping with said expensive cures/devices generously out if the kindness of their hearts. Maybe they're truly altruistic and also just idiots. Who am I to know ?
Truth : maintain a sanitary pool and you'll only need to replenish the FC lost to the sun, because your average residential bather load and environmental debris is a slim percentage of that, that you'll rarely even notice.
Move the pool indoors and you'll barely use any FC, pretty much solely from bather load. There is UV indoors and also things blowing in the pool, but it's exponentially less.
Mineral systems that help your algae problem by adding metals to stain you pool is like cutting off your nose to spite your face. *AND* You still need the same chlorine as a healthy pool, so why not just maintain a healthy pool that doesnt need algae control?
If you want easier than manually dosing chlorine everyday, a stenner type pump system will do so for you. You still have to source and lug the jugs, but you fill a 5 gallon (?) tank and the system doses as you tell it to, removing the daily chore.
Or get a SWG to produce FC for you, with no lugging, and it will add it daily as you tell it to, removing both chores.