Bean Animal Flow

[Wantsomemora Acrapora]

Can't seem to get my flow right. Too much water bypassing main drain into secondary. I have 1" Bean Animal on a 150 gal tank, main into Clarisea, gate valve wide open and return at 512 GPH.

 

[Reefer40b]

Can we see a couple pictures of your piping inside the overflow?

 

[Wantsomemora Acrapora]

Here are a few pics and a video. The main drains into a Clarisea. The video is of the secondary. All plumbing is 1", i.e. drain and return. The gate valve on the drain is wide open. Thanks for your help.