Hey there antoine bender , I tried following your link but couldnt find these pics there I'm sure they probably are, but I couldnt find em. Your problem is different than B2k's, Yours are mostly browning of the tips where his progressed through to a total necrosis of the leaf. Yours appears to me to be a magnesium defficiency. Its an easy one to tell because of the dark green veins with the lighter yellowing of the rest of the area and the burnt tips. Your 4th pic, on B2K's post shows its classic.
Hope it helps
Hope it helps
