The Oc filters are a snap to change, simply unscrew the top and no water spills.
You take out a 40 sq Ft 25 micron cartiage(this is more than enough for virtually any application), bleach for a day or so, rinse, dechlor and return(I'd suggest getting 2 sets of media, makes changing them easier).
OC's are easier than the plan you have.
The Volume of media for the bio and chem modules is pretty good also.
If OC or the Rainbow stuff does not do it for you, check out Aquaticeco.
They have larger systems with much better flow and pipe sizing.
As those pumps get larger, so does the sound/noise.
While some things might look neat, when you have to service them, you start dreading it.
Then you stop cleaning them etc.
Same deal with a Water change, make the set up easy for you to service.
Turn a valve to drain and back wash, turn another to refill and or backwash with clean tap.
I cannot drill through the wall or floor where I'm at.
So I use a little Giant sub pump to drain and fill by simply placing it in the tank to drain or in the bathroom to fill. Takes 7 minutes to drain and 8 to fill a 180 to 80% water change.
Imagine this with a bucket.
Some folks still think buckets are their only alternative and that hoses are not made longer than 20 ft
There are many options with filters when you start getting to these tank sizes. So the trade offs are very worth while over time.
You do not need to use hobby level equipment either.
You might be more familiar etc, but the end result is really the goal.
So learn now rather than the harder lesson later.
Regards,
Tom Barr