Every water facing surface in the entire aquarium system is a home for beneficial bacteria to colonize- including the mechanical filtration media. The BB will propagate to a level in balance with the food (Nitrogen compounds) available to the bacteria no matter what surfaces the bacteria has colonized on. Rinse the crud out of the mechanical filtration media in tank water instead of washing it thoroughly to keep from loosing all the bacteria that is on the media. Although you will still loose a considerable amount of the bacteria the remining will recolonize quickly.
Water flow is important to exposing the BB to its food source. This is why BB grows denser colonies on "biological" media that has a lot of flow through it.
I have a Nuclear cartridge filter that I tried for a while. Even with a good pre-filter the cartridge plugs way to quick for my tastes! I had to put the pump on the exhaust side of the Nuclear filter because the filter would always start leaking drips of water when the cartridge was full with the pump pushing water through the cartridge.
I switched to a Diatomatious Earth pool filter and couldn't be happier! Much cleaner/clearer water than every cartridge filter I have tried and MUCH MUCH less maintenance than all of the cartridge filters I have tried! https://www.monsterfishkeepers.com/f...filter.434493/
The rate at which a mechanical filter will clog is directly proportional to the surface area of the filter (assuming a constant mesh size). A DE filter coats the filter mesh with a layer of Diatomatious Earth that provides 100x more filter area than the mesh it is coating AND the pore size of the microscopic diatom shells is MUCH finer than the usual pore size of a cartridge filter... fine enough to filter out fungus, free floating algae, and free floating bacteria. When the entire surface area of the diatomatious earth is plugged you simple knock the DE off of the filter screen then turn the pump back on which recoats the screens with a fresh layer of DE exposed to filter the water. The regen of the DE takes me about 30 seconds to do with the DE pool filter I linked to above.
If you are set on using a cartridge filter many of our aquarist brethren highly recommend this cartridge filter that has about 80% more surface area than the Nuclear, is reported to be easier to change the cartridge in, and has MUCH less expensive cartridges available than the Nuclear. https://www.amazon.com/Pentair-R1725...303506&sr=8-68
I HIGHLY recommend a DE filter over a cartridge filter though!