  We present Co substitution effects in K$_{x}$Fe$_{2-y-z}$Co$_{z}$Se$_{2}$
(0.06 $\leq$ $z$ $\leq$ 1.73) single crystal alloys. By 3.5\% of Co doping
superconductivity is suppressed whereas phase separation of semiconducting
K$_{2}$Fe$_{4}$Se$_{5}$ and superconducting/metallic K$_{x}$Fe$_{2}$Se$_{2}$ is
still present. We show that the arrangement and distribution of superconducting
phase (stripe phase) is connected with the arrangement of K, Fe and Co atoms.
Semiconducting spin glass is found in proximity to superconducting state,
persisting for large Co concentrations. At high Co concentrations ferromagnetic
metallic state emerges above the spin glass. This is coincident with changes of
the unit cell, arrangement and connectivity of stripe conducting phase.
