I would think... as long as the water was the right temp, and you have a high Ph. However, I don't think you'd get much joy out of having cichlids in a pond, because they would hide a lot and be hard to see. Maybe if you just were in it for breedings sake, and had a show tank too?
someone on here ran a malawi pond in the UK. Expensive to do it though because of the climate. Heating that much water, outside, in the winter is not cheap.
Ludwig Venter (forum mod) lives in South Africa and has many tropical ponds in his garden.
so.....depends on your climate. But as said about, most tropicals are best viewed from the side on, not top down.