Flushing with FloraKleen is essential.
FloraKleen is a blend of acids in a dilute solution. It flushes excess salts with the power of osmosis. Many growers know to use it, as directed on the label, for the final week of growing. But it should also be used throughout the grow. Give it to plants once per month, or every 4 reservoir changes. Allow it to run through the system and irrigate the plants for the duration of one day. And then at the end, before harvest, run it for one week.
Every hydroponic grower works hard to avoid the dreaded "chemmy taste" that gives hydroponically grown yields a bad reputation. Growing aggressively, with high strength nutrient solutions, can leave mineral salt residue around your root zone, and even in the cells of plants. Watering plants with pure water can help prevent this problem, but using FloraKleen is a far superior method.