Water from coal bed methane production which is suitable for almost nothing, is ozonated in a reactor to oxidize the iron content from +2 to +3, that is from ferrous to ferric, and to oxidize the manganese content from +2 to +4. The water after such first treatment is run through a separation means and then through a rotating filter, and then subjected to capacitive deionization, to yield clean water, which is then treated further to adjust he sodium content to render the water suitable for domestic and agricultural purposes. Some of the produced water is run back through the capacitive deionization cells when no voltage is applied to clean the cells for the next voltage application cycle. Some of the water produced may also be run back through the separation means to help clean out the crud.