They also found scales and plastic ziplock bags.
Zhang pleaded guilty to the charge and at sentencing today his lawyer, Ron Mansfield, said his plea and remorse should be taken into account.
Mansfield said Zhang also had debts and used the drug but was undergoing rehabilitation so was unlikely to reoffend.
Zhang told police he was "looking after it for someone else".
Judge Neville Dawson said Zhang was involved in the proliferation of an "extremely harmful drug" and that needed to be taken into account.
Dawson said he also noted that Zhang's elderly parents in China were "clearly shocked and surprised" at their son's offending.
Zhang was sentenced to six years and nine months in prison.