I noticed that the first leaves started to have a brown and wilted tip, this happens with my new plants, however this one seems to be weak, I will try a flush with everything within the parameters, what could it be?
You might have given it a little to much food at the very start but if I were you I would transplant to a bigger pot it might simply be root bound, it looks a little lighter then average and could just need a bigger foot print...
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!