OK… You may lose all respect for us now (if you had any before)… But we are fizzy water-aholics. San Pelegrino is our drug of choice… But we would sink the boat if we tried to stock up for a 6 month trip (2 per day X 180 days = 360 bottles or 30 cases).
A soda stream type device might work… But it might be a challenge getting a recharge in Fiji… Where we are now.
Our solution was a modern take on a traditional device. The Matraad unit uses small co2 cartridges that we buy for 30 cents each in quantity. As a bonus it is much cheaper than San Pelegrino… And a few hundred cartridges fit in the space of 3 or 4 Pelegrino bottles.
It is important to drink lots of water in the tropics… and this makes it much easier.