Need to make a black water

[Aqualoon]

I have hard water too, I have tried driftwood and the peat methods. Push adjusting your pH to the side and look into lowering your kH and gH however you need to make sure that it's stable so using chemicals or products that adjust your water might become rather difficult. You could always invest into an RO Unit or as others have said keep your fish at your tap water hardness.