I tried to add water to the habitat consumables and i was given a message indicating that the water reserves were full (or something to that effect). It was a little confusing at first since the inventory had space. I think it is because water is represented as a bottle icon and I assumed it was discrete units and not just a "representation" of volume. Maybe change the icon to a water drop or maybe represent water differently within the habitat inventory management system. Not a big deal - just a suggestion.
Customer support service by UserEcho