Thanks for the explanation RichToyBox.
Buffering capacity was tested. 500 is penciled in in red.Iris


RichToyBox wrote:
KH is a measure of the buffering capacity of the pond, to maintain a
consistent pH or have a pH that is radically swinging. The KH must be
above 40 ppm or you are headed for a pH crash. A value of 100 is really
good. A value of 200 does not harm anything. If you have a bead filter,
then the value really needs to be over 100 but for all other systems a
value of 80 or better is acceptable.
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