I love all of you for this little discussion.
I didn't think about it in this detail actually, I was aiming for a "kneel to drink directly out of the bowl" - animation, which I think would add to the atmosphere of the desperate situation of losing sources of drinking water.
I think if you want to aim for realism there should be 2 containers like you guys suggested - the tank and the bowl, with two different qualities of water in it.
But I'm not sure if that's not overdoing it from a gameplay perspective. So I think I would probably just go for bowl-related stuff.
Would be kinda cool to be able to hide a firearm in the tank though.