DIY Durso Standpipe type overflow box

Has anyone done a DIY 'Durso Standpipe' thingy in their overflow box and sump setup ?
I need some questions answered.
I think it seems to sound like the most effective way of reducing noise coming from the overflow box. I want to drill my one tank and set up a sump system - but I really do not want the noise that comes with it. My other tank( a 500L ) already has a sump - and it's noisy, however, because it is in a unused area of my house, it does not bother me.
Somebody suggested that I put a piece of egg-crate over the bulk-head, then add a bunch of bio-balls and then take some filter matting and fold it zig-zag and place it on top of the bio-balls. This I can see as a potential problem as I would probably have to rinse out the matting on a daily basis to stop it clogging and reducing the amount of water flowing into the sump.
So, if anyone has done this, please let me know.
Dankie en groete!!

 

I've been using it , since BEFORE it even had a name!
There a these and other silencers for some time now
That they all function , is true..but each has a few disadvantages or maintenance requirements

For now you just need to know ...
The dimensions, I instructed you to make Overflow box,MORE than accommodates ANY Silencer technique of your choice
That's a big reason for the larger size

ALWAYS installed AFTER drilling, bulkhead fitting, Overflow Box is constructed.
This means NO rush, or panic:turtle:

So - What do you need to know?
A call is best