To elevate water from a flat biological necessity to a fun, bubbly treat, your best option—environmentally and financially—is a home soda maker. Since 2015, we’ve spent over 200 hours researching and testing 14 models (plus our own DIY version), and after drinking gallons of seltzer, we think the easy-to-use SodaStream Fizzi OneTouch makes some of the fizziest, tastiest sparkling water.