+3 - yes, adding bio-ceramic media can give a cartridge filter a better infrastructure to support beneficial bacteria. However, adding a sponge material would also provide that as well. The key is that cartridge heaters tend to 'miss the boat' if/when the cartridge is replaced, any/all beneficial bacteria on and in the cartridge gets thrown out to. With bio-ceramic or sponge material, the cartridge can be disposed of while the media remains. It is better if the water flow through the filter goes through the cartridge first, then passes through the ceramic or sponge media. In this way, you protect the bio-media from collecting decaying detritus.
Along these lines, if the reservoir is behind the cartridge, you might use a sponge pre-filter (such as the Fluval pre-filter) on the end of the inlet tube which would prevent detritus from fouling the ceramic media.
Another alternative worth consideration may be to replace the cartridge with sponge material filling the reservoir cavity. The sponge will be more effective and should last many times longer than a cartridge.
In one of my AquaClear filters I have full of sponge material. To prolong the sponges, I use scotchbrite like pads as a prefilter. This protects the sponge from direct detritus and when the pad(s) can no longer be rinsed clean, they gets replaced, leaving all the sponge material cleaner, intact and nearly untouched to serve as the beneficial bacteria colony infrastructure.