My first grow

@bluntzilla thanks you:) my fertiliser diet is pro chart of a nutri+ brand(i replace nutri+gold by pure black and i thrive by supermax b1). the first leaves turn yellow were the lower fan leaves and then it was spread all over the plant. several leaves are dead (most of the fan leaves). Also i have a littebit oïdïum on them but i treat them.. i dont know if it may cause yellow leaf..

Beautiful plants you've got there especially for first grow!! From the looks of it seems like your plant is suffering from a light deficiency, Nitrogen (N) most likely, if you could give more info about their diet, which fertilizers you're using, and a picture of the yellow leaves on the plant to see if its at the top or bottom of the plant that'll help determine that more precisely. Good luck and happy growing :)