Is there a way to raise KH without

[etr63]

Hi all

Is there a way to raise KH without raising GH?
My water out of the tap is

GH 7
KH 1
PH 8.6

After ageing the water for 24 hrs the PH drops to 7
I have read that a KH of 4 is the min. to keep PH stable.

The readings in my tank are
GH 7
KH 1
PH 6.8
I have to do no less than 50% WC daily to maintain this and I am worried about a crash in PH. I have tried crushed coral in the AC filter and it raised the GH to 16 and the KH to 2. So i tried a smaller amount of coral and it has no effect.

???

Earl

[Cosmo]

not an expert here, but, don't think there is a way to increase KH without also increasing your GH. If your GH is a major concern to you, you could mix in some RO water to lower the GH then add a buffer like Kent PH Stable to increase the KH - the GH would increase as well, but you'd be starting with a lower GH value due to the low GH of the RO water
Jim