SOMETIMES Spokane water is fine. Depending on the season, and agricultural activity, Spokane tap water can have huge nitrate and phosphate spikes. Then we have the city randomly "treating" the water system, which adds other nasties to the water supply. It's important to really know what's in your tap water, if you're going to use it. It's also important to test it, regularly, as levels of certain elements fluctuate, a lot. I'm not sure, but don't think Markee is actually on Spokane city water, but may be on a well. Here, it's also important to know exactly what's in your water, if you're going to use it, unfiltered. Also, on a well, elemental property of the water will fluctuate, according to the season and surrounding agricultural activity, which in Markee's area, could be significant.
Markee, yes you can buy RO/DI water, from Barbie or Kevin. However, in the long run, you'll be better off purchasing an RO/DI filtration unit. You'll always want RO/DI water on hand, for topping off, to replace evaporation, AND for making your saltwater.