Because of where I live, I need to use reverse osmosis water --for myself and the oscar tanks. What should I be doing to have a healthy tank if this is my water source?

i am not very particular about RO process but i do know it removed some
minerals and bacteria of water in the process. however, bacteria will thrive
in the tank once the other parameters are meet, thus, there will be no problem
using it.

Hey Dude

I use RO water for all my water changes, it beats tap hands down, but, as Paul says, the RO process removes some of the minerals that are good for your fish as well as removing bacteria and chlorine that are bad.
This can be remedied by putting back only the good minerals, you can do this with an additive, Tropic Marin minerals will do this.
Also remember that RO is PH neutral, so if you have hard water fish you will need to raise the calciate hardness.
Hope this was helpfull.

When i had a discus tank i needed soft water, and i live in a hard water area. So i got an RO machine. As said RO water makes water very pure. So what i had to do was mix it with tap water. So as long as you tap water isnt foul just mix it with your RO water. This will bring th Ph up to an acceptable level for oscars and will also add enough minerals into the water. It will save you from buying the minerals.

You just need to experiment with the ratios of RO to tap water to get your water good. Remember that oscars can live in quite a variety of water conditions