If earth is hanging in space how do oceans not flow down?

Gravity holds the oceans (and us) to the Earth's surface, as the Earth orbits the Sun at nearly 30 kilometers per second (67,000 mph!). There is no up or down in open space and everything is in motion with regard to everything else. The Earth's rotation (1000 mph at the equator) causes the surface and oceans to bulge outward, but cannot overcome gravity.

The concept that the earth is "hanging in space" is just a saying, like "the moon is hanging in the sky" or the like. The Earth has its planetary mass concentrated in the middle, and all things on its surface (and above it) are pulled "in" toward the center. We call the "inward" pull of the earth "down" instead. Water does, in fact, flow "down" on the surface, as objects are drawn toward the center of the Earth by gravity.

The oceans are actually slightly "pulled away" from the Earth by the gravity of the Moon, which is the main basis for Earth's tides, the movement of water from one area to another. The Earth's spin affects tidal flow but does not create it.