I'm starting as a Merfolk in a Pathfinder campaign that will suit being one. I will be in water relatively often. Would rations in my backpack be ruined by the water without the use of a waterproof pack?
Actually, the CRB rules do cover this explicitly:
Price 5 sp; Weight 1 lb.
The listed price is for a day's worth of food. This bland food is usually some kind of hard tack, jerky, and dried fruit, though the contents vary from region to region and the race of those creating it. As long as it stays dry, it can go for months without spoiling.
1) If it stays dry, it's guaranteed to last for months between Purify Food and Drinks.
2) If it gets wet, it is no longer so guaranteed, though it may still last that long, depending on your GM.
3) The contents depend on both region and race, so Merfolk rations from the Inner Sea Region contain different foodstuffs than Solar rations from the 7th Mounting Heaven of Celestia or Efreet rations from the City of Brass.
However, if by "ruined" you specifically mean the condition ruined that objects get when their hp goes to 0, no, your rations will not be ruined by exposure to water; only hp loss does that.
In general, you will also not need to worry about these sorts of things so long as your party has a Cleric; ruined and broken rations (and other objects) can be restored by mending/make whole depending on the source of the damage they took, while rations in particular can almost always be restored to prime condition via Purify Food and Drink. Since mending and Purify Food and Drink are both orisions and particularly useful, your cleric is likely to have them prepared at all times, and casting them is free.
In any case, asking your GM about the water survivability of rations from specific vendors before purchasing them in-game (or asking the the party rogue, if you have one, to source you specifically water proof rations) is probably the best way of doing this.
You should also note that Ultimate Equipment has specific rations for all of the various core races except humans and half-breeds, which usually cost around 2 gp. You may be able to talk your GM into designing an equivalent Merfolk ration which, in addition to explicitly being waterproof, grants some unique bonus.
By the rules? There is nothing in the rules about that explicitely. Thus logic has to be used there. If we go at it logically.....water profeness would depend on 2 things
- What food are the rations made out of
- Where and how are the rations contained
If the rations are contained in a bag of holding, or a waterproof bagpack there is nothing speaking against them surviving a trip into the water regardless what contents the rations have.
If on the other hand we take the rations themselves and add water to them.....it depends solely on the components of the rations if they survive a water trip or not. For example Merfolk themselves very probably also have rations....as they are most often found traveling under water their rations are made to survive this and probably consist of algea, fish, ... and thus would survive a trip into water.....on the other hand it is quite probable that these rations go bad quickly if outside of the water.
On the other hand what we land beings are using as rations tends to go bad quite quickly underwater.
Thus to summarize : If you don't have a water proof container or heat proof one, then if the ration was not designed to be of ingredients that a folk living in that environment uses it will go bad extremely fast. BUT this is only "fluff rule" as there are no hard..aka written down rules for that.