After Leaching: Crinkled, Pale Green, Lifeless Top Leaves

[mart!n]

3 days ago I leached my 10-week old, indoor, vegetating, Purple Kush plants for the first time. I used 2 gallons of RO water per plant. The final run-off water measured 60 - 100 ppm and 6.5 - 6.6 pH. I followed the leaching with a 1/4 strength nutrient solution (see standard solution details below). When each passing day the leaves at the top of the plants are crinkling up, turning pale green, and looking lifeless (see photos).

The plants are growing in 1-gallon pots, with Botanicare's coco fiber and watered from the saucers.

Nutrients include 1-2 tsp Cal-Mag, 1 tsp House & Garden's Cocos A, 1 tsp House & Garden's Cocos B, 1 drop SuperThrive per gallon of a mixture of tap and RO water. Final ppm range 900 - 1500 ppm and a pH of 6.0. Watering done about every 2 days.

A 432W Sunleaves florescent fixture with 8 VitaLUME T5 Bloom bulbs have been giving the plants light for 24 hours a day. The fixture is 1-6 above the tops of the plants.

The plants are in a 2' x 4' Hydrohut Silver Edition tent with one side open. The temperature has been around 77-82 degrees with a humidity range of 40 - 65%. No bugs.

Any ideas what might be wrong and how it address it would be appreciated.

Thanks,
Mart!n