So my father in law is going to Corpus Christi this weekend and he is going to be a darling and bring me back some Chicken Food Dog food for Gizmoon his way back, however... all they have in stock is the 18lb bag and the special for that right now is Buy one get one FREE! So I would buy 1 18lb bag and get another 18lb FREE! My question is ..since Gizmo is only 4lbs of looooooove...lol and (1) 5lb bag lasts him at least 3months do you think the remainder of the bag I open will go bad? I would assume the other "free bag" would be ok as long as it is kept sealed right?

... So that is my question... OHHH and they only have puppy left he will be 2 years old in July.... is that bad for him?