Tap water may be safe to use with homemade sugar water, depending on your situation. This is especially true if your water softener adds salt, which will also salt your hummingbird food.
Birds & Blooms reader Gerre Jaroch of Petoskey, Michigan, questioned her water before making a batch. My water softener was installed recently. Can I use that water to produce hummingbird sugar water? Should I use distilled water?
Using softened or distilled water with sugar water is bad for hummingbirds. Most water-softening systems increase water salt, which may harm hummingbirds.
Flower nectar contains natural salts, whereas pure water does not. If you can't find unsoftened tap water, mix sugar with bottled water (4 to 1). In addition to natural foods, they only need pure white sugar.
Hummingbird food should never contain salt. Avoid adding red color, honey, fruit juice, artificial sweeteners, or other additions to your hummingbird combination. It's tempting to add sweetness or nutrients, but they usually do more harm than good.