I have heard the larve eat roots but I just kill them and never found out. I also do not leave gross water
around in the pans and I use large enough pots that the surface stays pretty dry. Fly strips
will get the big ones but then you have to decide what route you want to go for the kids.
Some put sand across the top of the dirt and when watering place a bowl in the dirt so you do not
disturb the sand. I think you can also water the soil with neem some say to some do not like that crap on the roots.
Sorry I can not be more specific for ya. If no one else helps check out the bugs section maybe