Your 'theoretical' tank is theoretically overstocked

(I theorized that the fish were all of a large variety, especially the 17" pleco).
The buffering capacity of your "award winning" (and meaning 'stable') water will cause the pH restabilise to the original value.
The pH swings that you create from this attempt will be harmful to the fish.
(Not mentioning the impurities nor varying acidity levels here).
Run the filtered water thru peat to slowly lower the pH.
A stable pH is more important than a spot on pH.
Now go make some lemonade and sit back and enjoy the fish (theoretically).
Good question tho.
Dr Joe
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