Yellowing and curling for no reason...

Hi @JustifyGrower ,If the temperature of your grow is 18c it does not seem to be heat. If watering every day with fertilizers, there may be an excess of nutrients, just every 5 days. along with changes in PH and calcium and magnesium deficiency. PH that should be 6-6.5. it could also be the substrate too wet in your diary you say you water every day 0.5L, let the substrate almost dry between waterings, the roots without oxygen cannot feed and the plant blocks development and in the long term it dies. orient yourself by the weight of the pots, the substrate when it is almost dry becomes very light. in your case I would make a flush 3x the liters of the pot and apply a calmag solution with calcium and magnesium. good luck in flowering mate 👍