  We consider the heavy quark-antiquark potential in the AdS / QCD
correspondence, focusing in particular on a recently calculated AdS-like metric
deformed by back-reaction effects. We find that tuning the long-distance
behaviour of the potential leads to a discrepancy at small distances, and
discuss how to better constrain AdS / QCD geometries. A systematic comparison
of various geometries is presented, based on goodness of fit to lattice data in
the quenched approximation. The back-reacted geometry is seen to be
phenomenologically favoured over an alternative geometry with the same number
of parameters, although it does not perform as well as some other geometries.
