suggest that these two parameters could be easily tuned also in experiments, given that the concentration of a cationic surfactant could be used to reverse the propulsion’s direction and adding pH neutral salts could be used to control the propulsion speed [@Brown_Poon_SaltJanus].]{} In order to establish the relevance of hydrodynamics in this suspension, we study the collective behaviour of quasi 2D suspensions of spherical squirmers interacting via an anisotropic Janus potential, considering different interaction ranges, interaction strengths and hydrodynamic signatures. When clusters appear, we characterise their morphology as a function of the above mentioned features. [The objective of this manuscript is the analysis of minimal models that contain the essential ingredients of activity and steric interactions for heterogeneous particles. The scenarios we identify can be clearly correlated with the competition between self-propulsion, stress generation, and attraction among particles. It is true that phoresis is more complex and can also involve long range interactions among the active elements. Our results serve as a benchmarking scenario if phoresis is controlled by near field effects. In this sense, the systematic analysis we have carried out provides a valuable contribution in this general perspective. In a more specific perspective, this study also helps to 