Flame, I had a bottom drain until I caged the inlet off for a grass carp permit. I didn't want a blocked cage at the bottom of my pond, so I raised the inlet up. We had it 4' up from the bottom, and elevated 4'from the face of the dam. These pipes will move a lot of water and create a lot of suction, so I wanted to try to make sure the face of the dam wasn't compromised as DD1 said.
