some leaves thin, curled-upward, browning edges

Hello all,

I'm a newbie, on my first grow. I just switched from 24-on to 12/12 yesterday (600w HPS) , and today when the lights came on I noticed that about half my plants have varying degrees of a leaf issue that I'm unsure about. Some of the leaves have begun to curl upwards along the edges, with accompanying browning and a thin appearance. There's also a bit of yellowing on all of the plants, which I was told was signs of growth and not to worry. But this is new, and I'm concerned and confused.

I'm using rockwool cubes and flooding with Superbrand Grow Aqua, which I recently increased from about 350ppm to about 500ppm. My pH is in the 6.0-6.3 range consistently.

My rockwool cubes are soaked, I think I may have over-watered them 2 days ago (haven't watered since), and I am currently trying to pull out some solution by setting them on towels and hitting them with a fan.

Any help or advice would be greatly appreciated.



Here's a couple of pics...

http://img401.imageshack.us/img401/1328/dsc02363ha1.jpg

http://img401.imageshack.us/img401/8656/dsc02368bp3.jpg

looks too hot

I have very shitty dial up so can't download your photos....they're too big or something.....but overfert is the very first thing that comes to mind. However....a ppm of 500 SHOULDN:T be too much for your plants.

Revised: The Complete Guide To Sick Plants,pH and Pest Troubles - PlanetGanja.com

I think probably part of your issue is the rockwool and it's associated overwatering and/or ph issues.

I've never heard of Superbrand Grow Aqua so can't help you with any advice on it.

Good luck.

Quote:

---

Originally Posted by M.B.A.

looks too hot

---

My thermometer records the high and low temperatures (which I reset daily), here they are for the last few days, before and after turning them to 12/12:

83.7 / 79.3
81.7 / 79.3
83.1 / 63.1
73.4 / 69.3

it's currently 79.7

Quote:

---

Originally Posted by Weedhound

I think probably part of your issue is the rockwool and it's associated overwatering and/or ph issues.

---

I'm thinking it's related to the over-watering also, but I'm not sure. I wouldn't know what to do about it if that were the case... I just hope they'll recover! :(

And thanks for the link! :hippy:

You might put up a thread asking for rockwool information in the hydropnics section. Can't help you there because I don't use it myself....but lots of people on these boards do. :)

Quote:

---

Originally Posted by Baruce

My thermometer records the high and low temperatures (which I reset daily), here they are for the last few days, before and after turning them to 12/12:

83.7 / 79.3
81.7 / 79.3
83.1 / 63.1
73.4 / 69.3

it's currently 79.7

---

ok, then overwater/over-fert, I also have an electronic Hygro/temp

Quote:

---

Originally Posted by Weedhound

You might put up a thread asking for rockwool information in the hydropnics section. Can't help you there because I don't use it myself....but lots of people on these boards do. :)

---

I wonder if the rockwool has anything to do with it?

Oh, and I was wrong about the nutrient name, it's Supernatural Brand Gro Aqua (17-7-18)

Quote:

---

Originally Posted by M.B.A.

ok, then overwater/over-fert, I also have an electronic Hygro/temp

---

But what to do? :(

I think the rockwool IS your problem....and you need someone to tell you what to do with it. I know it's notorious for soaking up and holding water and needs all sorts of special care.....presoaking....careful watering times..gets screwy on the ph....etc etc. As I say, I don't use it so can't help you with it....but I'm sure someone else does and would know what to do. Somewhere around here I posted something about the stuff awhile back....let me check my old posts.

I can only search back 500 posts....couldln't find it sorry....google rockwool.....I think it's the source of your issues.