i dont think its from watering. i give each plant enough water to see about 20-30% runoff. then water again when the soil get pretty dry but not completely. i do this to collect the runoff for testing to make sure my soil ph stays stable.

any other suggetstions?
SoHigh420 Reviewed by SoHigh420 on . top leaves yellow/includes troubleshooting form What is your experience level? (first timer, novice, experienced...) FIRST TIME Your Equipment: .1) Type and wattage of lights. (MH, HPS, CFL's, tube fluorescents, LED's) 600W hps .2) Distance from tops? 18-24 INCHES .3) Reflector type? (cool tube set-up, bat wing, enclosed reflector, bare bulb...)COOL TUBE .4) Is there a consistent fresh air supply? YES BUT NOT THE FRESHEST:( .5) Do you have an exhaust fan and a circulation fan?YES .6) What are the bulb wattages, kelvin ratings, and Rating: 5