Dynamical regimes arising due to mutual interactions of oscillatory and excitatory modes of the Belousov-Zhabotinskii (BZ) reaction in a two-array and linear and circular three-arrays (with different arrangements of intrinsic connections) of identical continuous stirred tank reactors (CSTRs) coupled via symmetric passive diffusion/convection mass exchange were studied both experimentally and by numerical simulations. The coupling strength among individual CSTRs and the threshold of excitability of the BZ reaction mixture were varied systematically. Firing numbers (vectors) were used for classification of observed oscillatory-excitatory modes. Full spectra of firing numbers ranging from 0 to 1 were detected in all CSTR arrays investigated in experiments. The numbers of oscillators and excitators, threshold of excitability, and the way of coupling and coupling strengths within the array are principal factors affecting firing patterns of the array, Numerical simulations with the dimensionless three-variable Oregonator based model of the BZ reaction predict qualitatively well dynamical regimes encountered in experiments. Noisy coupling among the individual CSTRs due to hydrodynamical fluctuations is suggested to explain some of the observed differences.