Hi, yes its hard t say anything, But i would reduce the nutes abit, rise the HUmidity in giving her a " open dome" that means ahalved plasticbottle with holes in it. Think about ahumidifier. And well we just have to wat. Some strains havea slow start, but develop then very good if they leaves the seedlingsstage. 21 Degree is not too warm. If the pants have it warmer they grow faster