Yellow spotting and curling leaves??

hey guys, i posted pics in another thread about curling leaves on some rocklock clones of mine. i have some issues with my slightly younger clones now too, these are about two weeks younger and some of them are starting to get little yellow spots on the leaves. i dont think its nute burn, i have only fed them cal-mag one time and i water them with r/o water.

here are the two younger ones having the problems, you can see the one on the left has the yellowing and curling leaf tips and the one on the right has the little yellow spots.


heres the (2)two week older ones that have the leaves curling, but no yellowing at all, they look very green.


-someone mentioned dry spots in the soil, im now watering the entire medium.

setup details
-strain, Rocklock
-600 watt hps cool tube (about 20-24'' away from the plants)
-3 different soils to see which one produces the best/most.(mg,black magic,supersoil) so far the issue doesnt seem to be with with just one soil brand.
-watering with r/o water
-temp is 66-85 degrees
-humid 40%-51%
-i dont know my ph, i havnt started testing it yet.

any advice, ideas or input is appreciated


!!!!!MORE PICS!!!!!!! any ideas?

Have you grown clones with the 600w HPS before? And what lighting cycle are you doing?
It could be over exposure.

Although in general drooping yellowish patches on plants normally signifies over watering, which could be the case since it is affecting multiple of your plants. How much do you water?

It looks to be overwatering or poor drainage. Is your soil too compact?

http://tinypic.com/view.php?pic=1zg9ml1&s=7
http://tinypic.com/view.php?pic=t4whgg&s=7

how did you make out? i'm having the same.

MrWeedSocks said:

Have you grown clones with the 600w HPS before? And what lighting cycle are you doing?
It could be over exposure.

Although in general drooping yellowish patches on plants normally signifies over watering, which could be the case since it is affecting multiple of your plants. How much do you water?

Click to expand...

no, i've never grown clones with a 600w, this is my first grow. im running them on 18/6. i was thinking im underwatering them, i water about every two-three days, depending on the temp in the room. about the over exposure to light, i was kinda thinking maybe the light was too close, should i try and raise it too like 30-34'' away from the plants. i have a digital thermometer with the probe down at the base of the plants and it never gets really hot, 80*-85* at the most. thanks for the help, its much appreciated

cadeneli said:

Is your soil too compact?

Click to expand...

this could be the issue, but only with one of the plants, i remember packing one of the pots thinking it was a good idea to get as much soil in a three gallon pot as possible, now from what i've read that wasnt a good idea. when i can afford it im gonna buy that dalomite(i think that what it is) to help with the drainage. but im 99.9% sure this isnt the issue with the other plants though, they have really good drainage, you can hear the water draing/perculating in the soil and then after about 45 seconds a little comes through the bottom.

Your soil may be holding too mych water for too long. Its important that your plants roots get oxygen. If the soil is always wet and compact you are restricting the oxygen. If you don't have a moisture meter and you have an extra pot and extra soil, fill the pot with soil to the same level as the others and compare the weight of the pot to the others that have plants. I don't think that clones that size in that size pot should be needing water every 2 or three days. I water my mature flowering plants every 2 or 3 days.

ok so i havnt watered them since the 18th and they look to me like there not getting any better, maybe a little worse? idk, i took pictures with a better camera just now so you guys could see them better. the soil in two of them (the first two pics) is still moist from the watering 5 days ago! does that mean its holding to much moisture, all the other pots seem to dry out within a day or two. also the very last pic isnt rocklock, its this one big bud i have and i noticed its new growth is coming out really curled and the pot isnt moist or over watered at all. could this be calcium-mag deficiency and the other ones be overwatering/too much moisture?