young plant Leaves droopy and then mottled

[Bootsy]

This is my second grow and the first was done while i lived away, and in super soil, so i am a newbie. I was at a show and bought a packaged system from a canadian vendor (I assume i shouldnt give their name) growing system of nutrients in coco. started end of Jan. I have 6 plants started and four were picked to go to the bigger pots, but the other 2 kept alive so far. the healthiest looking plant, when i did a full watering (10% run off) for 3rd week, after which all the other plants looked fine, and this one started dooping. now 1.5 days later and it has what i would call yellowish mottling. i am still having problems getting light to right distance, but since the mottling seems consistent throughout, it seems that this isn't light related. .i did look at the plant problems area and couldnt find this one. 1. does this look like an obvious thing like over watering? the pots of choir take a few days to dry at all. 2. metal halide light. 600w dimmable set at 50% and now at 16 inches from the plant of concern (feels not very warm on my hand after 1/2 minute). photo of the setup wouldnt load for me. If anyone has suggestions, please advise. this damage happened really quick over 2 to 3 days. i will post more info soon as I am just home with a new hip and will soon have lots of time. cheers from Atlantic Canada

[Bootsy]

Oh yeah. Of the four plants in bags, the one in question is a Pineapple chunk) , there are two blackwater feminized, one is a mint chocolate chip (which the guy said was supposed to be female, but from what i read no guarantee). the pineapple chunk are from a bag, so not sure of their sex yet either, even the damaged one - so it could be a moot issue anyway. i have two spare pineapple chunk which both look good, but in tiny pots right now

[Bootsy]

more reading. i did do a 20% runoff this watering, but that was first time. wonder if she's got nutrient overload and I should do a flush of plain water?

[Bootsy]

for curiosity, this is the setup in my 3 by 3 by 5 ft tent. heater will ahve to move outside, and maybe humidifier. my back bedroom gets cold at night, doe to mid low 60s. humidity on cold days gets down to 22% but typically inddors in winter is around 26%. cooling is not a problem yet, and not expected to be for awhile

[Gingerbeard]

I'm going to throw this out there because I just had an issue with pH fluctuations. What I see in yours looks like what I had. Google some images for pH problems. Just because you're using plain water doesn't mean it has good pH.
My disclaimer is that I don't know always know what I'm talking about.

[Bootsy]

worrth checking . will look for the test kit. i didnt because last time it was in the right range. thanks

[Gingerbeard]

My machine water tests between 6.5 and 8.5. and I have no idea why the fluctuation. Sometimes a drop of pH down will do. Sometimes a drop is way too much.

[Bootsy]

Thanks. i did a flush with water corrected to 6.0, which is pretty close without adjustment when i add the nutrients. let them sit a day and then back to feed. the leaves that were mottled seem to still be alive, and new growth looks great as per the photo. thanks for the suggestion. i am still dealing with getting the lighting correct, but all part of learning. LST in progress. cheers

[keldog420]

imo.. you are over=watering and might be drowning roots.. should be dry

[mactheman]

just thinking maybe you should have mixed some perlite with the coco ,,,would have helped with drainage etc ....although coco does drain pretty quick the perlite would help with over watering if that was the problem ,,,mac.

[Bootsy]

thanks folks. it has pretty much cleared up with a flush and now amending the ph. i think i will start a grow journal that hopefully will be of interest to someone.