" We put in a water tank some years ago in Sydney. When we used...

" We put in a water tank some years ago in Sydney. When we used some of the water to top up a fish tank the fish jumped of the tank! We tested the pH and it was quite acidic. "

Well HD,

What can I say. That must be just because you live in Sydney where the pollution may be high. For, I use only tank water where I live for all my purposes, where I use wells and bores for the farm.

Now, my gold fish in the fish tank are just thriving and growing like mad, and like I have never seen before.

Could it be that the country air is better than the city air, or could it be that when the rain falls on your roof it washes down all the build up of smog and carbon dioxide emitted by cars and trucks in Sydney ??? Have you got a first flush installed on to your water tank ?

I really don't know. But I would like an answer.