My seven month-old puppy eats way too fast, he doesn't choke or anything like that, but I feel that he's not enjoying and obviously not even chewing his food, he can go through his plate (one cup four times a day for a total of 4 cups) of Alpo dog food in 10 seconds or less (haven't really timed it, but it's way too fast.)
He's fed strictly at the same time every day four times a day and he'll do that fast eating routine 99% of the time like there's no tomorrow.
While looking for tips on this I stumbled upon a WikiHow on a couple of tips such as turning over the plate, giving him food in multiple plates, doggy toy so he works more to get the food out of it, etc.
My question:
What is a proven approach to help a dog eat slower? While I do understand that he's a puppy and most puppies do this, I have a 3 year old dog who eats at a super normal rate, a 2 year old that eats a bit fast and this guy who is seven months and eats like he's getting a price if he finishes faster than everyone; so I'm looking for an answer with someone that's tried something with success with a specific approach.
He will usually wait for the other dogs to finish their plate and go see if there was some left over (there isn't any leftover 100% of the time but he doesn't mind checking always).
I feel that even my 2 year old dog should eat slower if possible, and the reason I mention this is because even if the answer might be "wait it out" I'd still like to know how to help my 2 year old female dog with the similar issue but at a bit slower rate than my seven month dog in question here as I'm assuming the technique will work in both scenarios.