Dalmatian pup diarrhea, dandruff and farts

Question
As you can tell by the title, our house hold is a bit crazy at the moment.  In
our home we have a 3 year old, 7 lb Maltese girl with long hair and we have a
new Dalmatian boy at 3 months, male.  Elli, the girl, was never much of an
eater of dog food.  But the number of treats and homemade food has
weakened with the introduction of the new pup.  She fell for the puppy food
(yeay!) and loved it.  The dalmatian boy, Schumi, came home with Iaams
naturals puppy food.  I did a bit of research and found Orijen dog food, a
grainless, premium food.  We took the slow switch, with the mix of the two
foods for over a week.   Elli had a really awful bout of diarrehea first,  I
blamed a bad batch of chicken jerky from Costco, but she is better now.  
However,  since the end of the switch and almost a week on the new
premium food,  the boy is leaking milkshake consistency, multiple times a
day, with very little control  (he was fully potty trained prior).  He also has the
worst, and constant gas.  Lastly,  I noticed dandruff just in the last few days.   
I am now thinking that he is allergic to something in the new food.  As I
research a new brand I am back on the Iaams puppy food until I find an
option.  This began yesterday.  But now I also stumble across low purine
recommendations for the breed.  I am leaning toward the Flint River Ranch
lamb and rice formula for adults...  but I really am just guessing again.  I was
hoping you could recommend a specific food, with the knowledge that the
maltese will most likely also be eating it as well.  Thanks!

Answer
Hi Danielle,

Wow, you do have a lot going on there. Of course you want  the best for your puppy, and it's  often difficult to find one food for two dogs - I have two adults of the same breed, and they eat sigificantly different diets.  With the breed and age difference in your household,  it's even more challenging.

I'd start with the puppy since he is having a big reaction (and constant diarrhea means poor absorption of nutrient at a time where he needs  it the most). There is a huge range of possibilities between the very high protein Orijen and the lower quality IAMs - I would be looking for a premium food with more moderate nutrient content. Some foods I like include

http://www.championpetfoods.com/acana/show-product.php?formulation=plb

but seeing as your puppy is a Dal, an ever more moderate food might be preferable:

http://www.innovapet.com/products/default.asp?id=1259

I prefer both of these to thee FRR, but again,  you need to find what works best for your individual dog. With the wide range of preium foods now available, there is not reason to have to settle for a grain based, questionable-ingredient product such as IMAs or Purina. Natural Balance, Wellness, Fromm - loads of truly good products ou there. I do think the Orijen is too high protein for your pup, but the Acana might work well and it is an incredibly good food. Then you can  switch the pup to one of the Acana Adult foods and your Maltese can eat it as well - if it agrees with her of course.

Hope this helps a little, get back to me if you have any  more questions.
All the best, Catherine