General use for water contaminated with petroleum is 1 gallon of Petra-Zyme per gallon of contaminate per 100 gallons of water. Allow 3-4 weeks for remediation.
There are many factors that can change the remediation time such as water type, oil type, wastewater, etc.
For example, a 1000 gallon pond contaminated with 10 gallons of petroleum would require 10 gallons of Petra-Zyme.