Diy overflow weir opinions needed

[FishOkay]

I have attempted to make this for a 2m x 2m x 0.8m 2500L (nominal) pond build I'm planning. I know it's not the tidiest but does that look like enough of an overflow. It's 50mm and will overflow through bulkheads on either side with a strainer also on the downward facing Tee fitting.
That length of overflow is 1.4m

 

[Reefering1]

Maybe drill a bunch of holes between the slots. If I'm understanding you post correctly

 

[RocketEngineer]

That type of overflow is very limited because narrow slots clog easily. Plus, the areas farthest from the outlets don’t have much drop so increasing flow just causes the water level to get above the slots which defeats the purpose. You would be better off with a box at both outlets or one continuous box. I learned this the hard way, don’t repeat my mistake.