85 is getting a little too warm.....you should not let temps go over 80 degrees in your room and that may be what is causing the curling edges. The other thing may be that your light is too close although 18 inches sounds ok.....but your plants may feel otherwise.
Weedhound Reviewed by Weedhound on . Need some Help Please I noticed recently that the outer edges of one of my plants are curling upwards. I recently topped the plant to promote lower branch growth and its working great. Im using a -400w HPS -2 fans, 1 medium sized pointed directly at the plants, 1 bathroom exhaust to help circulate the room -Plants are placed roughly 18 inches from light at all times -PH balance is normal -Moisture level is normal -I water them every third day, just a little -Heat is between 75-85 between dark and light Rating: 5