Need help with problem and am unable to find anything like it on any web site. I am 4 weeks into first grow. My setup is 3 plants, each in a 1 quart container with 1 68 watt 2700 k cfl / 3 28watt 6500 cfl surrounding each one. Soil is miracle grow organic potting soil. I water every 2 days and fert at 50% once a week with a 20-20-20 all purpose food. The problem appeared after the first 2 weeks with the oldest leaves developing browning on the tips and curling upward. I immeadiatelly flushed the soil hoping it would resolve the problem. The ph has stayed between 6-7 changing a little between waterings. I ve added lime to the soil prior to planting and have been watering with epson salt over the past 4 waterings with no success. The browning continues up the leaf until the entire leaf dies. I ve lost 3 sets of leaves thus far. It has appeared on all 3 plants, worst on the largest. The temp stays at a constant 78 and the humidity is steady at 52%, All the plants are roughly 4-6 inches in size. THey are all ak 48 feminized seeds. If anyone out there has had a similar experience i would truly appreciate any help that is offered. Thanks!