You're feeding this little one far too much... a 1.0EC is just much too much food. At this age, you really don't want to go over 0.6, MAYBE 0.8 if it's a strong plant... I would do as you say, flush her out and give her only 1/2 strength nutes if you give her anything at all... The brown, wilted tips are nute burn ...
Good luck!