This is Interesting a LOT depends on HOW we see the Xenomorph, in ALIEN it was more Bio-Mechanical, then we saw in the other Movies... the QUEEN looks a LOT LOT LESS say Mechanical than the ORIGINAL XENOMORPH... but then in ALIEN 3 and ALIEN R our Xenomorphs appear to be LESS MECHANICAL than the ORIGINAL TOO.
So we have to look at them as a ORGANISM.....
In the Drafts it was indicated the Xenomorph would EAT as it Grows..... the Neomorph in Alien Covenant was getting STUCK into Rosenthal.....
With ACID BLOOD i think we have to look at them Consuming Nutrients like a Spider or Fly would..... They may ONLY NEED a LITTLE to Survive and so we wont see Xenomorphs like Shredding a Human to the Bones...
The way i would Explore it would be that they Collect Dead Organisms that they have KILLED or also USE a Dead Host after the Birth of a Chest Buster. These Corpses are PLACED in the HIVE where the Hive Walls would SLOWLY Remove Matter/Dissolve the Corpses to Produce Nutrients that it STORES and the Xenomorphs can then OBTAIN these from the HIVE WALLS...
But they can also IF NEEDED be able to Obtain Nutrients from SUCKING on a Hosts if you get what i mean.... so the INNER JAW can Act like a Proboscis of a Fly/Mosquito etc.
