Macbrush 寫:
Actually, if you consider that fish and plants are used to the tap water's parameter, you can change as much water as you wish without any risk at all.
That is correct if tap water parameter is within acceptable range and stable, but that is not necessarily the case, especially in old factory building like where I am located.
However, a strong RO/RI water filter might help, I actually have checked that out before, on top of the high initial and running cost (which can be reduced if I shop in PRC), the water flow rate is so slow that I cannot finish changing water for all my tank within the time I am allowed to do in cafe, so I dropped that idea eventually.