Wow I think I know this guy or at least I heard about him from a co-worker. Poor guy came into the store to get a refund on the substrate. I tested my ph that has black flora max (2.5 gallon) and ph is 7.0 while the CRS tank is 6.8 being buffered down by bog wood and leafs.
He, I imagine lives close by and probably has similar tap water. The Ph this time of year goes up so if you haven't done a reset ph test of aged tap water might want to do that and then compare. Most people around western washington have either acidic or neutral water, but I have seen a few cases of people who live up north of seattle (rarely south) have very high 8.0ph depending on the time of year.