Sump/Fuge Question

[Shadowrider]

This is a picture of my eShopps fuge I'm setting up for my new tank. On the right side is a bulkhead where the drain line from the display tank will connect. Question is, I can't just let the water pour in from the bulkhead because of the splash and noise. If I use a length of PVC pipe should it extend below the water level or remain just above it. If it extends below the water level it will be quiet but will there be adequate water flow? Noise is not too much of an issue since the fuge will be in a closet in another room from the display. I would like a filter sock but the partition is kind of narrow and I haven't figured out how to hang one under the drain line. Would appreciate any ideas y'all might have.