sparkitsolution21 wrote: The pool water needs to be changed on regular interval to have fresh water.
Not really. Pool water only needs to be changed when it is no longer feasible to balance calcium saturation index. (Besides accidental iducement of organic or non-organic matter).
Sometimes even high amounts of CH or CYA can be rectified with levels of PH, TA, borates and salt, to achieve satisfactory CSI to protect the plaster surface.
It is not uncommon to have the same water in your pool for 5 or more years.