pup was dewormed..still has diahrea

Question
hi, we just adopted a (now 9 weeks old) male choc lab.  he has been de-wormed and had it's first set of shots.  the owners were feeding him wal-mart brand dog food if you can believe that.. we got some of it and are slowly working in Puppy Chow.  my question is that ever since we got him home he has had diahrea.  most of the time it is soft and mushy but very occasionally it will squirt out like a water hose.  the pup is VERY active, playful and loving and has a good appetite and plays great with our 2 y/o female lab.  after de-worming (done 2 weeks ago now) is it possible to still have worms causing diahrea or do you think the little guy is just stressed from being in a new environment and all that goes along with a new home?  follow up question.. if i buy de-wormer could it damage the pup? (can you de-worm too much)

Answer
Hello the kibble brands your using are to blame...ol roy and puppy chow are jnk plain junk and give puppies and dogs alike runny stools...they eat twice as much compaired to if they were eatting a high end kibble and therefore poop twice as much also forget both ibble and get him on something like Nutro or Blue Buffalo ...both are avalaible at petsmart.