Fish keepers tend to be very inventive, so what you presented comes as no surprise to me. It's important to note that a lot of fishkeepers go off the deep end to solve easily correctable problems.
Placing peat in the filter basket, or aquascape with a tannin rich bogwood like Maylasian, will lower PH naturally. On the downside, it will stain your water like weak tea. Really no need to work so hard adjusting PH except in extreme cases like certain well water situations. Most farm raised fish can adjust to a wide range of water parameters.