Best place for filter equipment?

I have just bought a 350L tank to set up a Malawi Mbuna Biotope.

I intend to filter my tank 6 times over with the overhead trickle filter and an external cannister (Tetratec EX1200).

Where would be the best place to position the filter components?

The trickle filter has an intake pipe on the right and outflow on the left.

The external has an intake pipe and a long spray bar.

Is it best to put the external's intake pipe on the left and spray bar in the middle at the top?

Thanks.

So you would have an intake pipe each side of the tank. One lower down to the bottom and one higher (about halfway up).

Just ask as well...will putting rocks around this pipes lessen their effectivness? or will the 'small particles always find their way'?

Thanks.