It may be better than tap water but you still have an unknown amount of solids in there. Reverse osmosiss or distilled is best but it gets expensive if you have a big garden. Let some of the spring water evaporate on glass and see if you have solids left over. If you do you could mix with RO or distilled.
spring water is good. many good companies will list dissolved solids on the bottle. check for that. tap water is usually too hard and will cause complications in growth, especially after seedling stage, entering veg.