Sick Plant, looks like maybe Mg of Zinc, but instead of yellow its White?

Pics: https://imgur.com/a/SVsGW

Strain is Candy Land @ week 5 flowering. Growing medium is grodan cubes. Using the CNS17 line of nutrients. Nutrient solution always around ph 5.8, ppm currently at 900. Temps are stable around 74 degrees with 45% humidity.

This pretty much developed overnight. During my last watering I noticed 1 yellow leaf and 1 big fan leaf in the middle of the plant that looked like it was showing some Magnesium deficiency, except the spots were white instead of just yellowing. I go in one day later and now the whole plant looks like its about to die.

Almost every fan leaf has this white Mg/bleached out look to it. The lower leaves are less effected and the upper leaves are the most effective. The leaves that are the worse have curled up gone crispy. The leaves that are completely effected also have this bleached out, completely stripped looked to them.

It almost looks like light bleaching, but in spots instead of overall. The plant is little over a foot away from a 600w HPS. All the other plants at the same height are doing fine.

Im really not sure what this is, or how to fix it.

it's not mg def. it could be your light is too close. could be something wrong with the genetics. CNS17 says that it contains all 17 nutrients so I'm guessing mg is in there. unlikely to be nutrient deficiency. how close is the light and what is the wattage? You have on leaf finger that is curling under. I wonder if you're over ferting cuz of that and the leaf is kind of dark green.

polishpollack said:

it's not mg def. it could be your light is too close. could be something wrong with the genetics. CNS17 says that it contains all 17 nutrients so I'm guessing mg is in there. unlikely to be nutrient deficiency. how close is the light and what is the wattage? You have on leaf finger that is curling under. I wonder if you're over ferting cuz of that and the leaf is kind of dark green.

Click to expand...

14inchs away from a 600w HPS. 5 other plants of similar size all under the same light, only this plant is having the issue

hard to say. if you put your hand just above the plant and can feel the warmth of the light on your hand, it might be too close but 14 inches doesn't sound bad. the other possibilities are genetics, or a nutrient problem. I don't have a good answer for you now.

Post a picture of the entire plant please. If that leaf is from the top of the plant I think we can assume light damage. If 5 other plants are the same exact distance and the fan is covering them equally we might assume that particular plant is stalled. But as soon as we start ass uming we really can make an ass of ourselves.

MeJuana said:

Post a picture of the entire plant please. If that leaf is from the top of the plant I think we can assume light damage. If 5 other plants are the same exact distance and the fan is covering them equally we might assume that particular plant is stalled. But as soon as we start ass uming we really can make an ass of ourselves.

Click to expand...

Here is a pic from this morning. About 9 hours after those last pics. And the problem has spread to the entire upper plant. it's like it's drying out from light burn and heat stress. Even though the light is over a foot away, the plants are in a flood and drain system getting flooded twice a day for 15 minutes, temp at the canopy level are always between 72-75 degrees.

Here is the pic from this morning
http://imgur.com/QliArNQ

man that is some crazy looking shit! im really sorry about this.....could you maybe top it and transplant into soil and see if you can save it?

Point source damage? Don't assault me for making assumptions, but tale a look at where you are tying onto the plant.

Looks like it was moved outside in the sun.