Most of us can't afford to live on some tropical island and go snorkeling with tropical fish all day. But with a small investment, we can bring a little piece of the ocean into our homes. Aquariums have come a long way since you had that goldfish in a small glass bowl. They've got high tech aeration and filtration systems, and aren't the leaky messes that kept them a niche item back in the day. Of course, caring for your fishes is a responsibility, and the more fish and the bigger the tank, the higher the cost to do so. YouTube user Ben at NightHawk in Light offers up an inexpensive way to get a few more cubic inches out of your fish tank and a better view of your fishy friends, using a simple scientific principle.