Hi,
GRHydro currently does not convert the primitive variables the ID thorns populate to the conserved quantities. However, since poststep is now scheduled also for initial data, it converts the conserved quantities to the primivite ones before evolution. This means ID thorns have to setup the conserved quantities to make this work. Currently e.g. TOVSolver does this, but it really should not.
HydroBase defines a group HydroBase_Prim2ConInitial exactly for this purpose: to have any evolution thorn scheduling prim2con routines it might need to use ID given in only primary variables defined in HydroBase. GRHydro does not schedule anything there.
I suggest to schedule the corresponding GRHydro prim2con routines in this group. I tried this and all testsuites still pass - but ID thorns no longer have to specify the conserved quantities anymore.
Are there objections?
Frank