Here are some links to DIY traps for aquarium fish. These traps and many variations have been around for a long time, so it is difficult to credit the original inventor, but I’ve used these websites to influence my designs.
The following website was the result of a search I did on “DIY bristlenose trap”:
Here’s how to make a DIY trap on youtube
This one mentions how to add a line to draw the trap up (I added the line before I saw this website, though):