white flies and leaf tips

OK so I have a little prob with white flies and im in the process of eliminating them but whats going on with my leaves? the sides are turning brown and the so I "upped" the nute intake and i burned the tips...anyways can someone please tell me whats going on and if its is a deficency? Thanks

If ya have fungas nats they will eat your roots and turn your plant yellow.

stop watering for a week and dry out soil it will stop all

Looks like nute burn homie. Check this link here and see for yourself.
http://www.drugs-forum.com/growfaq/97.htm