Water quality varies significantly from suburb-to-suburb and city-to-city. Tap water can contain various contaminants including chlorine, fluoride, minerals, and bacteria. You may have heard the terms ‘hard water’ and ‘soft water’, this refers to the amount of minerals present in the water supply. SA Water publishes complete analyses of the water supply system. They can be viewed here. In Adelaide, the average EC of tap water is 0.4-0.6.
Water quality plays a crucial role in a hydroponic growing system. When you have created the right environment, provided the right nutrition, and optimized everything else in the grow room, the rest comes down to water.
The main advantage of removing the existing salts from your hydroponics water supply is that nutrients are added only at the grower’s discretion, making growing more predictable and calculable. The only nutrients that are present in the nutrient solution are the ones that are advantageous to the plant. Nutrients can react with various contaminants in unfiltered tap water causing unpredictable results.