a diagnosis wich larvaes you have would be point 1 to clear
do you have closer closeups?.......
do you have adults? little black flies or any sign of adult flies=?
sure is,, you may have to fight them in eveery stage.
in egg, larvae and adult
but without knowing wich pests i can recommend you astrategy....
iam trhough alot of pests, and just get me per DM to go onn talking