With an 8 gpm machine, your draw rate is probably at least .5 gallons of soap per minute. 150 gallons would last 300 minutes, or 5 hours of straight use. With 2 machines, that's 2.5 hours of soaping per machine, per day. If the machines are running 7.5 hours per day, that's one third of the time for soaping, 2/3 for rinsing. Sounds about right to me, considering the type of work IB does.