Yes, hypoglaucemia is a big problem for this little ones, especially when they are so small. (9 weeks is really too young to have been placed in a forever home...hind sight's 20/20, eh?)
For the time being, I would stick with what your little one was eating--your furbutt is probably having a hard enough time adjusting to his new home without having to adjust to a new diet all at the same time. Once he has adjusted, then gradually switch him over to something new--bonus, that means you have time to do lots of research on what you think is a better food for him. There are links in a sticky at the top of this section that give you some info on free samples of verious foods to try out.
Here is a site that will link you to several other sources of information to help you research a diet--they examine home cooked diets, raw, and commercial processed food.
Dog Food Review Ratings
Just remember, what is best for one person's dog may not be the best for YOURS. You will have to do some trial and error runs--when you have found a good match for him, it will be quite evident from the results you see.