Ok I thought as much. Seems all the ones I see online are using the flex tube.

You could use a 90 degree fitting on top.

Are you asking if the kind of line is essential, or the line itself ?

If you're asking about the kind of line, it doesn't matter what you use.

I'm running a Mag 12 for a return pump without a bypass valve. The drains are 1". I close the full siphon about an 1/8th turn and a very small amount of water heads down the vented drain. Very minimal noise or bubbles at all. If I close the full siphon ball valve completely the vented drain turns to full siphon and takes over. If I manually block the vented drain and keep the full siphon valve closed, the emergency drain will still handle all the flow without flooding. I'm sold on this set up for sure. One thing to be cautious of is the depth of water the drains are in in the sump, too deep and the full siphon won't work, 1" worked for me.

I think he said how his name, Beananimal, came to be... With people misreading his shirt that actually said "Be An Animal".

A gate valve is the better choice but is only essential on the herbie. The extra standpipe on the Beananimal makes fine tuning less of an issue.