subscribed. lets start with the basics first, what is your pH your nutrient mixture is adjusted to? for soiless you want pH 5.8 and for soil you want a pH of 6.5 upward leaf curl is usually indicative of magnesium deficiency. you could try giving them some Epsom salts, id start with a teaspoon per gallon or 300-400 ppm. here is a cannabis leaf problem solver i hope this can help you.