Food and Drink.

[Kottin]

I can't find anywhere in CRB where it states how much food and water, per size PC, is required in a day.

[The Gleeful Grognard]

Not that I can see, although create food does explain the difference between sizes for your humanoids

"Most Small creatures eat one-quarter as much as a Medium creature (one-sixteenth as much for most Tiny creatures), and most Large creatures eat 10 times as much (100 times as much for Huge creatures and so on)."

I think they have moved away from specifics and have gone to days or weeks worth when it comes to food.
This is also supported by the starvation and thirst rules on pg.500 and how subsistence is also binary in its result.

[lordcirth]

Kottin24 wrote:

I can't find anywhere in CRB where it states how much food and water, per size PC, is required in a day.

Under Gear, page 288, Table 6-9:

Rations (1 week) 4sp Bulk L.

Waterskin 5 cp Bulk L

There is no longer description for Rations given below, but:

Waterskin: When it’s full, a waterskin has 1 Bulk and contains roughly 1 day’s worth of water for a Small or Medium creature.