Is there any leaf discolouration ? If there isn't I doubt its a defeciency. You already said your Ph and watering schedule is fine. My best 'guess' would be toxicity in one or more nutrients preventing uptake of another or the soil is constantly saturated preventing the roots from getting any oxygen. I could be completely wrong.
MegaOctane12 Reviewed by MegaOctane12 on . AHH help. Super leaf curl Hey guys. 2 of my 3 plants are showing strange leaf curl. The whole leaf is curling downward not just tips. Also the leafs curling seem to be just the budding leafs not the fans. 1 Ph is good. 2 Watering on schedule. 3 Been watering past few days with only water. no nutes. 4 Bottom of pots dont seem to have roots trying to bust out. 5 Plant seems to be sativa. Plz help guys. Rating: 5