What are you feeding, the bags will give you a guideline on how much the dog should eat. How much does he weigh? In general, a four pound dog needs less than a 6 pound dog. Sometimes, the wrong food can cause eye stains and tearing. I switched food once and Joey developed really bad tearing problem, so I switched back to his normal food. Some people have luck with Gerber’s baby water in the gallon. It's purified water with many of the minerals taken out. For some reason, excessive minerals can cause problems. This is a good article on the causes and cures of eye tearing.
Tearstains. If you are trying to grow a long coat, a weekly bath is a must, some breeders do it more than that. Always us a shampoo made for dogs, and rinse a minute more than you think you need to. A good conditioner is important too, because it conditions the skin, as well as the hair. They need a more through grooming about every 6 weeks to 2 months.