This mechanical media basket holds filter floss pads and Polyfil where water enters the sump on my 90 gallon rainbowfish aquarium. It is made from a plastic tupperware container that I up-cycled from a package of lunch meat (after washing thoroughly). I drilled about 30 holes into the bottom of the container using both a 1/8" and 1/4" bit to spread the flow evenly across the tray.
This is a modification to the original design for my DIY 20 gallon sump. The container fits perfectly into the larger basket that houses a coarse sponge and previously held my mechanical media. A smaller media tray keeps the flow of water concentrated into a reduced surface area, which allows me to use less mechanical media. It also facilitates changing the media, because it is easily removed and replaced, as shown in the video below.
The bottom of the basket is stuffed with Polyfil which is then covered by a piece of filter pad media that is cut slightly larger than the aperture of the container. The clear sides allow me to see when the media is dirty and needs to be changed. This is a dirt cheap DIY mechanical filtration solution for a sump; I covered the use of Polyfil and some other cheap DIY filtration solutions here.