Without a CSV you can’t put in a large enough tank to stop the cycling. A 202 only holds 5 gallons of water, a 251 only about 12, and even a 350 only holds 35 gallons. With a house that uses 500 gallons per day or more, that is a lot of cycling just to refill a big tank. And have you seen how much those big tanks cost?
With a CSV any tank larger than a 4.5 gallons size (1 gallon of water) is a waste of money, space, and heat. It doesn’t matter if the pump comes on every time you flush a toilet. How many times a day can a toilet be flushed anyway? What is important is that the pump stays running the entire time you are taking a shower, using a sprinkler, or any time water is used for extended periods, which is what a CSV makes it do. This takes out hundreds of cycles per day, so adding back in a few cycles for single toilet flushes doesn’t add up to enough cycling to need a larger tank.
Also with a CSV, when water is being used anywhere in or out of the house just before, right after, or during the same time a toilet is flushed, the pump does not see an extra cycle for the toilet. Even when a toilet is flushed multiple times in a row, you would have to wait 3 minutes between flushes to cause an extra cycle. Flush a toilet every 2 minutes and the CSV will just make the pump stay running continuously until you are finished flushing, even if you flush 100 times or more.
Of course you can use a CSV with as large a tank as you want. But after you see how the CSV works you will kick yourself for wasting all that money on a larger tank. As long as you are using more than 1 GPM, the CSV makes water go right past the tank, straight to the faucet(s) being used. It doesn’t matter if it is a 1 gallon or a million gallon tank.
With a CSV an 80 gallon size bladder tank is large enough for an entire city with 50,000 people, so you certainly don’t need one that large for a single house. In the past all you could do was install as large a tank as you could afford or had space for. With the CSV having proved itself for over 22 years now, that hasn’t been the case in a long time.
Big tank systems are outdated. You just as well use a horse and buggy instead of a car, or an old typewriter instead of a computer as to use a big tank instead of a CSV. Using a big tank WITH a CSV is like having a car pull the buggy you are still riding in.
The Pside-Kick kit with the CSV1A and the 4.5 gallon size tank will cycle the pump less and deliver stronger constant pressure than a room full of big expensive tanks, and is only a fraction of what a big tank cost.