Thank you guys for the input.

Kev, altum...my nightmare. I can't even control the PH in 2ft...and how to control it well in 6ft? Since the PH drop liquid is not the permanent solution. As you know the PH will still raise after days of PH drop liquid. Unless i have a PH controller in my 6ft.
I think standy said the spraybar..is the output of the filter. You can see how strong is the flow with so many bubbles.

Joe, SA or CA still not my taste yet. Perhaps i have a pond like in kev house. Then only will house in few pairs of them. Ya...the drift wood with rock n sand bed look kinda weird for malawi. So, no drift wood. Malawi still my cup of tea.

The haps...damn.. they are beautiful. For a 6ft, how many pieces do you guys recommend? Saw Fossochromis Rostratus, Prtomelas spilonotus Tanzania, Nimbochromis Linni and Aulonocara Stuartgranti "Mbamba" in petfrd.com. They are another beautiful too.
I don't mind to get all of them...but each species with 2 pairs. So, what species you can get nowadays? Please pm me the price for pair. thx dude.