This is the best design I could come up with for mine. Water flows from right to left. First chamber is a filter sock off the inlet pipe followed by filter pads. Second chamber is bio (note that it is held up off the bottom as that's going to be water (not wet/dry)) with heaters sitting under the tray (bb actually will do well with a bit of extra heat as long as you don't bake them). Then the bubble trap followed by the third chamber for the pump.
