Storing tap water

Thanks for the input. I have no idea what the KH is of the stored water or the tank water, is there a test kit i can buy for this ?
I do not have a proper tank up and running at the moment as i have a new tank on order and have just two fish in a bucket with my old filter running ready to seed the new tank. So i can not really do any more proper comparisons until my new tank is up and running.
 
AquariaCentral.com