gernerally one might use distilled water, tap water (after being set oout for 24hs), ect for seed germination. Conside this Mineral water can be used in soaking seeds (water method), paper towel method why ? -- using mineral water is a cheap way of keeping a stable PH enviroment. Tap water can vary laot in terms of cheminal coomposition and PH. The ideal PH for water when germinating is PH of 7. If one is having issues with germination consider mineral water