"Greg G." wrote in message
...

Greetings,

When I originally set up my current 75g planted tank, the tap water
here was pH ~7.0 with a gH of ~2 and a kH of ~1.5.

Now, a year later, the water coming from the tap has a pH of 8.3!
Even though the hardeness levels have remained the same.
snip
What on earth are they adding to the water that is causing this?
snip

Caustic soda is what my municipality adds to bump the pH up.

NetMax