Something is very wrong RDWC (PLEASE HELP)

IgrowUgrow

Well-Known Member
I have 2 seedlings one BF Critical Kush + DF Cheese and they are in a recirculating DWC, I have 2 air pumps and 3 inch air stones in a 10-12 gal reservoir with a submersible pump that is connected to my top feed line. I am using a 600w MH for veg and a 600w HPS for flower. I am using the lucus formula with general hydroponics at around 1/2 strength and I just recently added calmag and 29% H2O2 at 3ml/gal but I still don't see any new growth on either seedling. They are light green and not really growing at all, btw the PH has settled down now and staying steady at 5.9 with my ppms at 700 the bottom of the net pot yet. I have my top feed drip set at every 6hrs for 15mins each time just to keep the medium moist. The water in my res is about 2" from the bottom of my netpot so the bubbles splash the bottom and keep the bottom layer of hydroton moist constantly. I don't know why the growth is so slow it looks like some kind of lockout but I don't understand what it could be when everything seems to be optimal. The water temps are still in 60's and the grow room temp at canopy level is between 74-81 so I just don't get it please help.at 700. The roots are thick and white and have fuzzy roots growing off the main roots but have not reached the bottom of the net pot yet.
 

IgrowUgrow

Well-Known Member
This is what one of them looks like it isn't yellow but it is this size and just hasn't grown any at all in a week or more. It is 2 weeks from first leaves and doesn't even have first true set of leaves yet. It looks exactly like this really with the leaves slightly curled down and the 2 single leaves turned yellow. I just don't understand.

 

IgrowUgrow

Well-Known Member
The other seedling looks just like this but without the brown dry patches it doesn't have any spots just this color green and same size.

 

IgrowUgrow

Well-Known Member
Btw I just brought the ppm's up to 700 I started with a ppm of 250 and slowly brought it up by changing the reservoir water and making a slightly strong nutrient batch each time until I reached 500 ppm's and after 4 days without any res change the ppm's went up to 700 so I guess they have been drinking water and leaving the nutrients behind.
 

warble

Well-Known Member
Two week old seedlings at 700ppm? Sounds a bit much. Drop that down to around 250 ppm and they should start growing again. Enjoy.
 

IgrowUgrow

Well-Known Member
No sign of nute burn at all, they just are not up taking all the nutrients so I have to keep an eye on my ppm because it will rise every few days if I don't top the reservoir off. I would have dropped my ppm already but I haven't seen any signs of nutrient burn at all.
 

IgrowUgrow

Well-Known Member
The reason my ppm is so high is because I have been reading different peoples nutrient schedules in RDWC and most keep their EC between 1.2-1.8 from 2 weeks old until flower so I have mine at roughly 1.0-1.4 EC which is 500-700ppm
 

*BUDS

Well-Known Member
Too much light for seedlings, start them under a much smaller light. You shouldnt be using soil in a dwc system, use rw cubes to start next time. Also are you using H202 in the res every 4 days to stop disease ?
 

IgrowUgrow

Well-Known Member
Too much light for seedlings, start them under a much smaller light. You shouldnt be using soil in a dwc system, use rw cubes to start next time. Also are you using H202 in the res every 4 days to stop disease ?
They are under the 600w MH but it is dimmed to 50% and the light is about 18" away, I did start them under a smaller light but I really don't feel like my light is the problem. Don't you think if it was the light it would have either bleached or burned them to stress them out, they look like they have some kind of nutrient lockout. I got the seed starter plugs from the hydro store they are called rapid rooters I am not using soil the photos were example pics because I don't want to use my phone to post pics on this site, so I went to google images to find a pic that looked exactly like my seedlings. I add 3ml/gal at rez change and roughly every 3-5 days I add a cap full to the rez to prevent disease. Thanks for your response.
 

IgrowUgrow

Well-Known Member
Too much light for seedlings, start them under a much smaller light. You shouldnt be using soil in a dwc system, use rw cubes to start next time. Also are you using H202 in the res every 4 days to stop disease ?
Technically they are not even seedlings anymore they are over 2 weeks old just very stunted.
 

IgrowUgrow

Well-Known Member
.1 ec is only like 50ppm did you mean 1.0 ec that is like 500ppm. Btw I checked out your grow and I see alot of myself in you if you look at my sig below click on IGUG bubble bucket and you will see that also. I tried ghetto stealth and it was ok but I have a grow tent now and I am much happier with the tent but still enjoyed my ghetto grow.
 

IgrowUgrow

Well-Known Member
I tried starting a seedling at around .1ec and it never got past its first set of leaves either.

Oh yea and in your pics I noticed you have light leaks well during flower any light leaks will be a serious problem, I don't know if you fixed the light leaks already or not just trying to help a brotha out.
 

Doobius1

Well-Known Member
700 ppm is too hot for seedlings. Lucas recommends RO water as well. I start my seedlings at about 400ppm. Lucas formula full strength with RO is only 600ppm
Get your ppm down you will see new growth
 

IgrowUgrow

Well-Known Member
I'm not using RO my tap water comes out at nearly 300 ppm, so what am I suppose to do just not use nutrients? I used my water before with no problems. You said you start your seedlings at 400 I started mine at 500, just after a few days it goes up past 600ppm. Thats not that big of a difference is it? Btw technically they are over 2 weeks old so I don't know if that would really be called a seedling.
 
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