Many of you still ask me why airplants don't need much water to survive. It's quiet unusual for most of the plants as we know them.. All the secret is hidden in airplants porous leaves!
Tilandsia's breath the water and the nutritious via the leaves so if you travel and you are unable to water them they will kind of take care of themselves :)
However please don't forget that we don't have a level of humidity that you usually find in the jungle and once you are back from your travels airplants will be more then thankful for 30 min bath and more regular water spraying ( 1-2 per week ). Convince to give them a try ? check how beautiful they can look in your apartment.