challenging research field. Exciton-polaritons (for brevity polaritons) are mixed light-matter excitations in a microcavity (MC). [@Carusotto.2013; @Deng.2010] At finite quasi-particle density, several fascinating phenomena like superfluidity [@Amo.2009; @Amo.2009b; @Sanvitto.2010] and the formation of quantum vortices [@Lagoudakis.2008], were discovered. This allows for numerous novel applications like optical parametric oscillators [@Baumberg.2000], polariton lasers [@Schneider.2013; @Bhattacharya.2014] and logical elements [@Bajoni.2008; @Steger.2012; @Ballarini.2013; @Anton.2013b; @Sturm.2014], which are usually restricted to low temperatures. However, polariton BECs even at room-temperature were observed in MCs based on wide band gap materials like GaN [@Christopoulos.2007; @Christmann.2008; @Daskalakis.2013] and ZnO [@Lu.2012; @Li.2013; @Lai.2012] or organic materials [@Plumhof.2014], paving the way for technological applications. At the moment, experiments in these materials are significantly affected by disorder [@Christopoulos.2007; @Franke.2012; @Trichet.2013], and a thorough understanding of the impact disorder has on experimental observables in a polariton BEC is called for. In contrast to conventional BECs, occurring for example in cold atom systems, polaritons have a finite lifetime, which gives rise to unique properties of the condensate. Nonetheless, there remain similarities, for instance, in the absence of disorder quasi-long range order of a two-dimensional polariton condensate [@Roumpos.2012; @Chiocchetta.2013; @Spano.2012; @Spano.2013] and superfluidity is theoretically expected [@Wouters.2010; @Keeling.2011] and experimentally observed. [@Amo.2009; @Amo.2009b; @Sanvitto.2010] 