  In a 1996 paper, See$\beta$elberg, Trautmann and Thorn modified Gillespie's
(1975) Monte Carlo algorithm which is used to stochastically simulate the
collision and coalescence process. Their modification reduces the storage
requirements of the simulation by several orders of magnitude. However, their
modification creates unphysical and potentially fatal conditions when used with
common initial distributions. We identify those conditions and propose a
solution to maintain physically real conditions for all state variables during
the evolution of any initial distribution.
