I just got a prescription for Debantic from Canadian Poultry Consultants, they were so great at explaining the process. 10g of powder/1L of water for the chickens, individual chickens are 35mL each. Coops are 20g/1L. Spray both chickens and coop with one of those handheld garden sprayers. No egg withdrawal, retreat in 14 days if required. Be SUPER CAREFUL with this though it is a poison to humans. Wear your PPE (safety glasses, chemical resistant gloves, mask/respirator). Look up the SDS and follow it carefully.