Its probably more natural water then you'd find at the dam. If you use it for saltwater, make sure you add all the right ingredients but vigorously test the water before you use it.
i've had tanks for 10 years i've neever tested the water for ph,nitrates,or anything else is it really something i should consider more...i've never lost fish expt for old age.I have a giant gourmi 24 inches long,a community tank(55gal) and a 90 with a 8 inch red devil,4inch jack dempsey,and a stripped convict.my lfs told me if's it's not broke don't fix it.keep doing what your doing cause it seems to be working....