Ok, so I am new here and to cannabis cultivation in general and want to thank you for any information that you give me. About 12 days ago I went to the club and got 10 GDP clones, about 5-6" tall, rooted (with virtually/literally none showing) in 2" rockwool cubes. I placed them in my recently built aeroponics system with a feeding cycle of 1 minute on, 4 minutes off, as was recommended by my local hydro store guy. They are being fed the recommended ratios of Advanced Nutrients Grow, Micro, Bloom nutrients for vegetative growth (2,2,0.4), but have cut the dosage to 400 ppm total (rather than 950), with the water starting with 20 ppm. I also check and adjust the ph 2-3 times a day and keep it between 5.5-6.1. Although I did have some ph problems in the first 36 hours because I was using tab water which had 550 ppm without nutes and wouldn't hold a ph to save its life. The reservoir and room are also kept between 68-72 degrees at all times. I have them under a 1000 watt HPS light. At first I started them about 4-5 feet from the light and moved them to 14-16" away from the bulb over about 3 days. However, after looking like dog shit I thought that perhaps it was from the light so for the past 4-5 days, they have been about 2.5-3 feet away from the light. Almost right away (48-72 hours) from the time I got them, they started looking bad. Many of the leaves were turning yellow, the tips were turning brown, and many were droopy and/or curled down. Only three of them have started to grow healthy roots out of the bottom, but 2 of the 3 look like they are on the verge of death. Also, I was stupid and super uber squished the root area when I shoved the 2" SQUARE rockwool cubes into the 2" CIRCULAR net cups......so I'd guess that having their roots smashed into tightly packed rockwool isn't good. On the 7/10 that weren't showing good roots out of the bottom I removed the rockwool completely yesterday. And just so you know (in case it matters) I have two clones that are a different strain and are not in any medium (just the neoprene insert) and they are doing terrific. Anyways, thanks again for the help and let me know if I forgot any info. The pics below are fairly representative of the health of the plants. Well, actually I'm sad to say that the pics kinda make them looks better than they do in real life. Thanks again.
Looks like light bleached, but could be combo nutes some of my strains will only take like 850ppm at 18 to 24''. Lot of people start with a 1/4 for nutes. 400ppm doesnt sound bad but depending on how it was grown to start with that may be its first nute of any strenght.
Thank you very much for the advice. I think that it could be the lights as well, but I don't really know anything. I've read the Marijuana Bible from cover to cover, but have no real world experience with growing. Again, I truly appreciate your taking the time to help me. And anyone else who feels inclined to help will also get a huge thank you.
Too close to your light. I also use 1000w HPS lights in my grow. I promise that they will respond to the light being raised. 1000w HPS are hot, I hope yours is air cooled. Even if it is air cooled, I would think that you had them close enough to heat stress them. Back your 1000w HPS about 4' off your plants.
Yes, the light is air cooled with a 6" 430"ish" cfm inline fan. Thank you for the advice, I have pulled the light back to 4' away. Can I ever bring it lower again or is 4' where it should stay? AND!!!!!!!! I thank you very much PrplHz for your advice.
4' off is too far for 1000W's. I say more like 24-30". And I hate 1000W's. Too hot directly underneath them. I love 600W's. Good luck they do look crispy.
A 1000w HPS puts out so many lumens. It will vary based upon the bulb, but, you are probably running 150,000 lumes, so there is no need for you to get too close. I am just speaking from experience. My light is a little more than 6' off the floor. My plants are in 35 gal. rubbermaid tubs. That means they are about 2' off the floor. This translates to my light being a little over 4' over the plants. I am running a SCroG, with my screen 9" above the tubs. I have no plans of lowering my light. 1000w HPS is strong, you can do quite a bit with that light . Of course my light is not air cooled like yours. That just means that mine gives off more heat. You are still pumpin out lumens.
Thanks again for the advice. I had no idea that it was supposed to be so far away. I will keep it at a safe distance from now on.