full procedure
Wel, the full procedure would be to remove all the parts to a bucket. Pour out the body of the filter and wipe it down with a paper towel or a fish safe sponge or wad of filter batting. then take a filter brush and clean the impeller, the tubes and intake cage. If you are being thorough, get some white vinegar and wipe the top of the filter and any water spots. I like to shake out the biowheels though some people don't, I think they get bio-slime inside them and then may not turn if they get unbalanced. I wipe off the endcaps also. There is plenty of bacteria safe in the fiber of the material after I'm done. I toss the parts back into the bucket to hold until I reassemble, not submerged in water, just wet and dripping. While the tank drains for a partial water change, I tend to plants or gravel, remove the hood and wipe the glass with vinegar to remove spots. I wipe the tank glass of algae if necessary. Then put everything back together and fill the filter with tank water. Plug in and let it go.
If you never wipe the body of the filter, eventually stuff will break free and float around the tank. The thing is, after the filter cartridge or padding insert if you use that, any gunk cannot be caught, all you have is the biowheels and they are not going to catch gunk, they might even add to it.