two opposite “jets” aligned along the rotation axis of the disk, modeled by cones with an aperture angle of $20^o$ and extending up to distances of about 300 kpc. The adopted expression for the power of the jets is essentially that given by the simulations of Koide et al. (2002).

Properties of simulated SMBHs
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One of the main aspects of the growth of seeds by gas accretion concerns the fact that masses do not increase continuously. In the hierarchical model, galaxies are assembled in the filaments of the cosmic web or in the junction of filaments where clusters are formed. In filaments galaxies may capture fresh gas that will feed their central black holes. Gas may also come from merging events. However, from time to time the gas in the central region is exhausted and the process of growth stops until a new episode of gas capture is able to replenish the vicinity of the black hole. In fact, the amount of gas in the central regions of the host galaxy is controlled by the capture processes and internal processes like star formation and feedback from supernovae and the black hole itself. In figure 1 the individual growth of 