Is this your tap or tank water?
If your talking tap water you can lower it wiih peat by aging it first by putting the peat in a filter bag and running a powerhead to pull water thru it in a separte container (50g plastic tub etc.) and check the chemistry daily till it's where you want it.
Secondly, you can put it in a HOB in a filter bag as above.
If you aready have fish in this water, change the pH very slowly, quick changes are worse than high pH.
Get a good quality peat w/o fertilizers or chemicals (WholeEarth type stores).
Dr Joe
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