Some words more about softening the water. A common method of ion-exchange, where the calcium and magnesium is exchanged with sodium ions (the same principle where salt is added in the dishwasher) is not good for the plants. Boiling the water will soften it, but the method is practical only if very small amounts are needed. There are some water softening products for plants available, they are easier to use than vinegar in water, which has to be tested for pH, but more expensive. I use water passed through a Brita filter (has a softening effect) for my indoor potted plants. We use that water for coffee and tea as well in Basel, where the water is middle hard. In Spain the tap water has chlorine, heavy metals, salt, nitrates etc. in it, so a filter for the entire house is essential, otherwise all that stuff will get in the soil with the irrigation. There is not enough rain water to collect which would be obviously the best for the plants.