Hi Androal-
I can always find new and improved ways to be wrong but I believe that Maurice kinda thought up this stuff with the K1. His website will give you good reading
read this and look around too (including plans to convert a vortex and build an air ing) and here is a video from somebody's board.

(kinda long load)
Static K1 cleaning from Maurice
The RMatala is 6" thick each premade section and what I have learned from reading is that the deeper media will have little biological activity, repeated shallow media can be more effective. Stack it and aerate like crazy.
The idea with the springflo in the first chamber is twofold. One, you've already got it. Choose which you would rather clean- brushes or springflo. Don't aerate the springflo, no. Stop the flow, shake, drain, don't clean, just rinse. Two, I am making the big assumption that you are pulling, or pushing maybe, more than 2000gph through this filter series. Its max rating is 2000gph so mechanical seperation could be improved with the springflo , thereby improving the rest of the filter's function.
Now, this means nothing if you toss both the brushes and the springflo and line up your chambers as #1 static K1 (daily simple effective maintanence) #2 K1 moving bed, #3 R-maltala.
A good air pump is a beautiful thing.
Mickey the windowman