Mantis's point is that the tap pH is 6.6-6.8...but the aquarium tests 7.2-7.4.
My suggestion, Mantis, is to get a bucket of tap water, cover it loosely, put in an airstone (to outgas CO2
) and see what the pH is after 24 hours.
Flourish ferts should not be raising pH at all. I suspect that, due to winter months, your tap water is holding more CO2
than usual, thus giving a 'lower than true' pH level immediately out of the tap. by outgassing the CO2
, you'll get a better pH reading, which I'd guess will be more in agreement with tank pH.
that said, 7.2 isn't bad for a tank at all. Unless you have specific fish that need a more acidic water, there's no need to freak out over a 7.2-.4 pH.