This video is to explain a little on what I think is the science behind how the DIY overflow siphoning system works.

Not sure if the explanation is 100% clear but it also shows the progress of the shrimp tank and how does it looks now after the “upgrades”.

The following had been modified
1. added a net over the overflow opening in replace of the sponge to allow more water in & prevent shrimps from going into the overflow tube opening.
2. Added a new plant & neon tetra fresh water fish
3. Cloudy water finally clears up after the upgrades & reduction of food given :D
4. Added a basket at the sump filter to disperse the water effectively over the sponge filter
5. Added a moss plant & 55 Watt light at the bottom sump