What is reverse osmosis or deionization that some growers use?
These are just processes that remove most of the dissolved minerals from water. Many orchid growers with poor quality water will use one or the other to produce high quality pure water for use. To repeat the warning above for pure water users, you must use a complete fertilizer including calcium and magnesium, and be careful of the pH after adding the fertilizer. For more details see “Water Quality Issues for Slipper Orchid Growers”.
