Hi there, I am new to this site, but I have read some posts here and I believe you experienced members can help me with my problem. This is my first post and my first grow too.
My seedlings have 10 to 15 days but a week ago I have started nuting them 1/4 and 3 days ago 1/2 but they have started to show yellow in the leaves. I think that it is lack of Mg, but I am not so sure
General info of the grow room for a better diagnosis:
I use Flood and Drain system from IWS, medium is hydroton, I flood and drain 4 times a day for 15 minutes (they are not overwatered or underwatered as I have kept watching all the time and leaves are not droopy neither up). PH is in the 5.5 to 6.0 range, generally 5.8 The CE was at 0.60 to 0.65 when I was giving 1/4 and now is in the 0.78 to 0.80 range (the manufacter recommendation at full is 1.50 for veg) The nutes is The Dutch Formula 1, 2 and 3 part from Advanced Hydroponic. The water temperature is 68, room temperature is 70 to 74, RH is around 50 (a litlle low, but I am trying to work on it with a humidifier), two oscilating fans are moving the air all the time, plus i have extractors with a passive intake, fresh air is moved minute after minute. I am using 600watts HID lamps with cool tubes and pro adjust-a-wing spreader. I have read several guides of sick plants, and my seedlings look like thay have lack of Ng, but I am not sure because it is suposed to have it in the nutes
Before changing to 1/2 nutes solution I did a flush with ph´d water and one more detail, until today they were in 24/0 light cycle, but I have started today with 16/8.
Please, give me your opinion what should I do to confirm it is lack of Ng, or what is your guess??
Thanks to all

Sounds to me like chemical burns showing on your leaves... do you have any pics to show? That would make it alot easier to tell....

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I believe the man told us not to eat the f*@#in apples, never did I read "Dont smoke the forbidden herbs" LOL.....

what is the content of the nutes your using, what percentages i mean?

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I believe the man told us not to eat the f*@#in apples, never did I read "Dont smoke the forbidden herbs" LOL.....

Hi There & Welcome to green Passion. Great to meet Ya. Some of the Hydro guru's should be by shortly to lend a hand. From reading I have done, you may not be flooding enough. I could be wrong. I am a dirt grower.

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Cheers!!!!! Shinningwind
current log @ HGS
Shinningwind's Outdoor Adventure/09

Hi, and thank you for the fast response. MG, I thiink it is not nute burnt as only two are REALLy suffering the yellow leaves (when I mean yellow, I mean it) and all seedlings have the same time, they are 19, so why are two more affected than others. I promise you I will have some pictures in the morning.

i very well may be wrong, im a soil girl as well. Did you say you just changed the light cycle???

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I believe the man told us not to eat the f*@#in apples, never did I read "Dont smoke the forbidden herbs" LOL.....

Hi Shinningwind, thanks. I believe I am doing the right feeding time, I am hand watering the rockwool (a very tiny water amount, jsut to keep it wet not damp) and 4 flooding. It takes 15 minutes flooding and 15 minutes draining. It is the time adviced by the maker, Intelligent water System (IWS). And when I was doing 18 minutes I realized some leaves were dropping, with 15 minutes all serrated leaves are horizontal. Once again, thanks

MG, thanks, you right I did changed the light cycle today. So far it has not effect on them. Here is the page of the nute maker, Advanced Hydroponics maker of Dutch Formula, tomorrow I can give you more details of the nute elements, and pictures of course

No Problem 4evergreen. Somehow or other. We shall all figure this out.
Your light is a safe distance from your babie's ?
You say you have sufficient air flow...
Some strains can be particularly PH sensitive.. The range you have said seems..That it should be fine. What do you use to adjust your Ph level..?
What strain are you growing..? Yes picture's will help when you get the chance.
Your temps sound right on...
I'll be back...lol

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Cheers!!!!! Shinningwind
current log @ HGS
Shinningwind's Outdoor Adventure/09

Shinningwind, thanks again, the lamps are at a save distance and I am monitoring the temperature on top of the expanded clay with a Temperature Climate Controler, which shoots 2 oscilating fans and 5 extractors in case it is needed, so at 25 inches from the seedling it never get hotter than 75. I use the PH down from Grow Technology, here is the link ph Up and Down - Growth Technology

Let me correct myself, when I explained my situation in the OP I have mentioned that I thought it was lack of Mg when I wanted to say Ng, as I have read some Sick Plant Guides and my small seedlings look like yellow and lime green similar to the pictures in those guides with lack of Ng, but of course I need the experienced growers´ opinion as I have read tons but i have grown zero, and experience is everything (IMHO)

Here is the PH bottle I use:

Say Bro, Is there any way you can get some pic.'s up??,,,I'll have to go back & see what all is going on, but sound's like you are right, it's either low nitrogen our low on magnesium, if not both. For the mag. you can get Cal-Mag, Epsom Salt & Molasses. I haven't ever used the Advanced Nut.'s but you would think it had enough nitrogen.

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Hi all, thanks again for your warm advices. Here is the info of the nutes:

Dutch Formula 1 (Grow) 25-12-50. The manufacturer recommended dosis is 1,5ml per lt (6ml per galon), I have used 1/2 as they are seedlings
Nitrogen 2.5%
Phosphate 1.2%
Potasium 5.0%

Dutch Formula 2 (Bloom) 00-50-35. The manufacturer recommended dosis is 0,75 ml per lt (3ml per galon), and I have used 1/2 amount
Azote 0%
Phosphate 5.0%
Potasium 3.5%

Dutch Formula 3 (Micro) 45-00-10. The manufacturer recommended amount is 0,75ml per lt (3ml per galon), I have used 1/2 dosis
Nitrogen 4.5%
Phosphate 0%
Potasium 1.0%

are all the seedlings the same strain? if not (lets say you used a grab-bag of seeds), those 2 particular strains could be sensitive to your nutes or pH. Rockwool is known for raising pH over time....did you soak the rockwool in pHed water of 6.0 before putting seedlings in? if not some strains could be sensitive to the high pH of the rockwool medium. also, what kind of water are you using? tap water, R/O water, distilled water, filtered water? if the plants are yellow all around you might just need a kick of nitrogen.

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Here is the picture of my grow room set up

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set up.jpg (83.7 KB, 41 views)

Pictures of one of them, you will notice it is turning REALLY yellow. In another mesage I will post pictures of another seedling (I am having problem uploading pictures)

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	baby 1.jpg (79.3 KB, 66 views)
	baby 1b.jpg (73.8 KB, 21 views)

Another picture of the same seedling

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baby 1c.jpg (57.5 KB, 13 views)

Pictures of another seedling. In this one you will notice its leaves are like a tiger, yellow and green stripes

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	baby 2.jpg (55.4 KB, 9 views)
	baby 2b.jpg (46.3 KB, 6 views)
	baby 2c.jpg (46.6 KB, 15 views)

One more picture of seedling in previous post

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baby 2d.jpg (42.9 KB, 8 views)