I don't think there's a break in period.
My first tank (75gal) has a canister filter on it. I use just the normal-ish media. Sponge, larger sponge, bio pellets.
The canister filter I have is a big pain when it comes time to change media. I haft to shut part of it off unscre a really finicky clamp. Then tanke the top off getting water everywhere. Then cleaning out the media and that stuff.
Then gotta put the top back on rescrew the hose.
It's kinda a annoying process but at least I don't haft to worry about water not going into overflow and I can have a uv filter attached.
But I would prefer a sump or an aio like I've got on my 80gal bedroom tank.
Also gotta hang a protien skimmer on the back of the tank where everyone can see the crap in a little cup.
I could get a picture of the whole setup but lights are off right now.