Using a durso drain for a herbie drain

[mook1178]

Hi all

I have a 75 gal tank drilled for a durso drain. The holes are 2 different sizes. I am wanting to do a Herbie drain. I am going to use a HOB return and use the 2 holes as the drain and emergency drain.

My question is do I make the larger hole the main drain or the emergency drain? I can see pros for the larger being either as well as the emergency drain being either.

 

[mook1178]

bump