High Gh/PH/KH

I'm curious as to why you are worrying about those parameters, it has great buffering capacity and guppies and plecos will be fine with a pH of 8.4 and the other readings. If you were keeping wild Altum angels of Uaru fernadezepezi those parameters would be detrimental, but not most bread and butter fish. In fact many people that keep African rift lake species would be envious of your water.
 
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