Tank unit and liquid ejecting system having tank unit

A tank unit for supplying liquid to a liquid ejecting apparatus, the tank unit comprising:

• a plurality of liquid accommodating containers disposed in a row, each of the liquid accommodating containers including a main body having a concave shape defining a side opening and a film that blocks the side opening, the main body and the film at least partially defining a liquid accommodating chamber for accommodating a liquid, an air accommodating chamber and a communication portion, through which an air in the air accommodating chamber is introduced into the liquid accommodating chamber, the main body including a facing wall that faces the film across the liquid accommodating chamber, the facing wall having a wall larger than the side opening, the liquid accommodating containers being disposed such that the film of at least one of the liquid accommodating containers is covered by the facing wall of an adjacent one of the liquid accommodating containers.