Plain coconut water is literally just the water on the inside of a coconut. So if you can get coconuts at your grocery store you can get coconut water. I also found this recipe on how to extract and flavor the water: http://www.eatnapplay.net/2013/03/04/make-your-own-coconut-water/.
About Celebrity Solstice. Celebrity Solstice is a large ship, carrying 2850 passengers and 1246 crew, and sails from Sydney, Australia and Auckland, New Zealand.
The Process: Celebrity Cruises automatically adds gratuities to the onboard Seapass account. The suggested gratuities added to your account will be $13.50 per day, per passenger ($14 for Concierge Class and AquaClass cruisers). Suite passengers will pay $17 per person, per day.