I use Seachem Matrix for bio and whatever filter pad the manufacturer recommends for mechanical. Some will tell you to go buy filter floss/pillow batting, but for the ease of fitment, known particulate trapping capabilities AND the fact you can rinse the pad over and over again I find it an acceptable spending over indulgence.
What type of cichlids? I find in most of my Rift lake set ups (Malawi and Tanganyika) that I barely use mechanical in my canisters, and load them up with ceramic rings. This is so because I find that there is really not a lot of free-floating debris.
In my South American tanks, I use a 75/25 mix of mechanical/biological, mostly because there is alot more debris (plant leaves, etc.), and that I don't need as much biological because there is so much surface area due to plants, which also help in breaking down amonia as much as the rest of the bio media I would've used.
Since you'll probably be really only be housing Mircrosoreum, Anubias, and crypts, you're more than fine with loading it up with biological filtration. I use a tonne of ceramic rings, and then a small course filter sponge. Since you wont be using stems and the sort, I find that you need as much bacteria as you can to help break down the waste and sort.