Success with tap water

[BCOrchidGuy]

Our water in the gvrd has almost no dissolved solids, even discus breeders need to harden the water a tiny bit.

I do not believe there is any reason for rodi water. Buy an inexpensive deionizing filter to polish your water. Our water has chloramine I believe, you can remove that with prime or the DI filter.
On the bright side if you do go with rodi filters your membranes should last a very long time as there are no carbonates or bicarbonate to remove