Not sure what you are referring to as the overflow chamber, but it's not gonna fill past the lowest route out.. in this case the drain if I'm not mistaken.
The point of the hole in the white piece is to allow air to get in to help with noise, not for water to go through. It floats by design.
To put a stand pipe in, personally, I would remove the bulkhead and either attach a pipe directly to that, or start a fresh from the bulkhead up, pretty mu h because of the risk of leaking where joini g new pipe to old, having a piece of pipe to join. 2 halves is gonna reduce the amount of flow and you want to make sure the flow it can handle is more than the pump will return.
You are gonna need to measure the size of the pipe and/or the drilled holes on the aquarium to know exactly what size you need; maybe you can work it out from the physical size of the bulkhead.
Its likely gonna be easier to read up on overflow/stand pipe design.. it's primarily a saltwater thing, do you are likely to find more info on that side of the hobby.
The point of the hole in the white piece is to allow air to get in to help with noise, not for water to go through. It floats by design.
To put a stand pipe in, personally, I would remove the bulkhead and either attach a pipe directly to that, or start a fresh from the bulkhead up, pretty mu h because of the risk of leaking where joini g new pipe to old, having a piece of pipe to join. 2 halves is gonna reduce the amount of flow and you want to make sure the flow it can handle is more than the pump will return.
You are gonna need to measure the size of the pipe and/or the drilled holes on the aquarium to know exactly what size you need; maybe you can work it out from the physical size of the bulkhead.
Its likely gonna be easier to read up on overflow/stand pipe design.. it's primarily a saltwater thing, do you are likely to find more info on that side of the hobby.
