seeing as you are new, its okay to ask, thats how we all learn...
but go ahead and take it from me first... so you know for future reference... without details on setup of nutrients, lighting, i.e. how you have cared for your plant in detail etc... or even a pic of the plant it will be next to impossible for anyone to diagnose your plant accurately...
[FONT="]However, if they are babies as in 4 wks old or younger then they usually wont have this deficiency which is characteristic of a Mg Magnesium deficiency, where the lower leaves yellow and may even turn white while veins remain dark green, and the blades die and curl upward...
but that was just a simple presumption on you post of curling upwards part... so post a pic and you may get much better diagnosis from the wide range of experienced growers on RIU...
welcome btw too
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