The feedback between the intra-cluster medium (ICM) and the active
galaxy in the cores of galaxy clusters is evident when combining X-ray
and radio observations. Numerical simulations permit to study the
mutual evolution of these systems in detail by putting together
information from observations and analytical models. In this
presentation the dynamical, MHD and chemical effects of FR II radio
sources on the ICM and its magnetic fields are described, along with
two simulation in this context. I will show our models of the
evolution of the metals in the ICM of a cool core cluster; from the
continuous metal formation at the central galaxy, to their advection
away from the cluster's core due to the effects of powerful
intermittent jets. 
On the other hand, we simulate the magnetic fields in galaxy clusters
with a spatial spectrum structure and random phases. I will talk about
the synthetic rotation measure maps we do with these magnetised
clusters and about our 3DMHD simulations of radio source feedback on
these magnetic fields.