External overflow box set up

[dreamcatcherr9]

Reposting in this section hoping for clarity.

I attached three (3) examples. For the standpipes in a Herbie or Bean Animal style set up.

Emergency is left completely open and unobstructed. But primary and secondary I see a few different methods. Does it matter?

I have seen example of left open, covered with strainer and connected with PVC elbows to “U” back down.

Will any work, just a preference?

 

[lapin]

Setting up external overflow box

I attached three (3) examples. For the standpipes in a Herbie or Bean Animal style set up. Emergency is left completely open and unobstructed. But primary and secondary I see a few different methods. Does it matter? I have seen example of left open, covered with strainer and connected with PVC...

www.reef2reef.com

 

[lapin]

What works for me always is,
Open emergency higher than the other 2.
Main drain is lowest with "u" and flat strainer and gate valve.
Secondary is higher than main but lower than emergency, and also has a strainer. In my box, the hole in the top of it will get covered and become full siphon, before the emergency drain is needed.

 

[badluckman]

I use the left one with 3 pipes, the bean animal style and it's dead silent with 800gph flowing through 1.2 inch pipes with a valve on the siphon. Feels good with an emergency pipe that's (hopefully) always dry too.