Mite infestation

[Yolksetta]

Power washed the coop 5 days ago. Discovered mites when doing so. Most had been sprayed out with water but close to coop. Sprayed elector PSP. Inside and outside the coop I had only seen one or two mires since then went out there today in the middle of the day and the coop door is covered and tiny mites. Why? Should I spray again?

 

[GodLovesU]

There are probably mites on the chickens themselves. This article has some information on treating mites.