Looking for sump design help

[Craigdillman]

Hrm still haven't found out one that i like , i seen one time a fish store in the states had all there sumps overflow down into some live rock then up and onto a "tray/shelf" that had the layers of padding then down through and up again over a wall then into main part

Just wondering how long I should make that shelf ? And wondering about bracing the filter sock shelf is just floating but if i made that longer would it need to be braced

Or maybe i should just use the existing shelf and redo the filter sock holes to allow the water more time to flow over the pads rather than down the filter sock holes