Planted Tank Guru
Join Date: Jan 2010
Location: Contra Costa CA
Think about the flow of water, and follow the debris.
Use the coarser media first, then the finer.
I use a coarse sponge, purchased for a large pond filter then cut to size over the intake of my larger filters. I use Aquaclear filter sponges over the intake of smaller filters.
This means the first mechanical filter in the system is the largest cell size.
Inside the filter the mechanical media will be medium and finer. This keeps them all in order so the debris is filtered out in a way that keeps all the media in use, and it usually all plugs up about at the same rate.