Water with too many minerals can be unhealthy and even hazardous, such as when a plugged-up super soaker erupts with an entire quarry's worth of geodes. Prevent a geyser of amethysts with today's Groupon: for $12, you get home delivery of three 2-liter cases of PureFlo Purified Water (a $23.94 value) and one 30-count box of Crystal Light packets (a $9.98 value; a $33.92 total value) from Pure Flo Water Company. This deal is valid for homes within a 45-mile radius of 92101.

Winner of the Excellence in Manufacturing Award from the International Bottled Water Association, Pure Flo Water Company delivers fresh, clean, purified water—drawn from a sealed, granite aquifer 900 feet below the ground—to thirsty above-ground homes. Each batch of water passes through a 5-micron filter followed by a 1-micron filter before reverse osmosis removes impurities such as minerals, solids, and curse words. Electrodeionization further filters the water, which is then sterilized with ultraviolet light and bottled before reaching its destination. This deal includes a one-time delivery of three 2-liter cases and one 30-count box of Crystal Light beverage mix, available in a variety of flavors.