DWC Autos are not growing at all, please help!

Hey guys,

I really could need some advice. This is my third attempt on DWC (first 3 plants died of too little water, next 2 of drowning in too much water). Currently, I have 3 Autos in my DIY DWC setup. Two of them are two weeks old, and the third one is the survivor of the second attempt, which is about 3 weeks old. I know that they look horrible, but I don't know what I am doing wrong. I grew them in rock wool until they developed some roots and then planted them into the DWC system. From there on, the first week, I top feed them by hand until the roots poked out of the system. I have an air gap around 2" to the net pots. The system holds about 20 gallons and the air pump pumps around 10 gallons/minute of air into the nutrient solution. I start giving them a 1:1:1 ratio of GHE TriPart as soon as they developed clear deficiencies for the yellowing of the first leaves and of course the plant in the middle. I also added about 1 ppm of sodium hypochlorite into, which is far below the value that some others recommend in this forum. The nutrient solution smells fine and the roots seem ok. My problem is that the plants look very unhealthy and also have an extremely slow growth. I have done a lot of research about DWC before I started, but it seems like this does not cope with my lack of experience. I am using a BlueLab EC-pen and my PH-meter is calibrated and should work fine. I marked some things below, which could be red flags in red, and also which things I think I have done right in green. Would you guys start over or try to save them since they are autoflower? Do you spot anything that could have caused these issues?

The hydroton looks moist because I sprayed them a little with tap water.

1. Are you growing from seed or clones? Seed (420FastBuds Autoflower)
2. How old are your plants? 14 Days (one plant 21 days) from seed
3. How tall are your plants? 1–2 inches
4. What type of hydro system are you using? DWC
5. What brand/type of nutrients are you using? GHE TriPart for Hardwater which is around 2 years old but still looks the same as when I bought it and has no signs of crystallization, also there is no expiry date on the bottles (I still don't think this is the issue here but correct me if I am wrong)
6. What is the Ph of your nutrient solution? 5.9
7. What is the PPM/EC of your tap water? 150 ppm (700 scale) / 0.2-0.3 EC
8. What is the PPM/EC of your nutrient solution? 260 ppm (700 scale)
9. What is the temperature of your nutrient solution? 68-70 °F
10. Does your PPM/EC show a rise or fall when you do your daily PPM check? No
11. Does your pH show a rise or fall when you do your daily check? No
12. Do you foliar feed or spray your plants with anything? Only once with tap water
13. What kind of lights do you use and how many watts combined? LEDs 100-150 Watts (Mars Hydro SP 3000 @ 50%)
14. How close are your lights to the plants? Around 10" as you can see in the picture
15. What size is your grow space in square feet? 4 feet x 2 feet = 8 square feet
16. What is the temperature and humidity in your grow space? 75 °F and around 55-60%
17. Have you noticed any insect activity in your grow space? No
18. How much experience do you have growing? Around 8-10 grows all in soil
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although i would have culled and started over in your shoes you can try increasing the feed to 300 ppm
I think I will wait until Saturday and see how they do. Do you think they had too little nutrients?

I am also considering bad genetics, but I killed 5 out of 8 so far. I don't know if 420 FastBuds is a bad breeder or am just a terrible grower, at least in DWC. Do you spot any issue with my parameters?
 

terpedup83

Well-Known Member
i would just increase the feed just to see, at this point cant lose, are you removing chlorine from water? hydro is not forgiving like soil, are you leaving a nice air gap between the nutrients and the roots? are you aerating the nutrient solution good? and yes you are right can just be dud beans, also res temp is important, keep it cool, add a cap of peroxide to the res too
 
i would just increase the feed just to see, at this point cant lose, are you removing chlorine from water? hydro is not forgiving like soil, are you leaving a nice air gap between the nutrients and the roots? are you aerating the nutrient solution good? and yes you are right can just be dud beans, also res temp is important, keep it cool, add a cap of peroxide to the res too
I am using a very strong air pump with 6 air stones in the reservoir (20 gallons of water / 10 gallons of air per minute) and I left a 2 inch air gap, so aeration should be fine. The temperature is in the optimal range of 68 °F. I did not remove chlorine, since my tap water has almost no chlorine in it. I added a little bit of bleach but way less than other people do (1-1.5ppm) to keep the reservoir sterile. I do not have hydrogen peroxide.

Yea I dont have much to lose, this is true.
 
I added a little bit of CalMg, about 30 ppm. My tap water has around 40 ppm calcium and 15 ppm magnesium. I have my lights on during the night from 19:00 to 13:00. This keeps the temperature pretty stable.

Could it be that the nutes are too old? I always thought mineral nutrients can't go bad but maybe im wrong.
 

Boatguy

Well-Known Member
I added a little bit of CalMg, about 30 ppm. My tap water has around 40 ppm calcium and 15 ppm magnesium. I have my lights on during the night from 19:00 to 13:00. This keeps the temperature pretty stable.

Could it be that the nutes are too old? I always thought mineral nutrients can't go bad but maybe im wrong.
Just need more roots in the solution. Have you been top watering at all?
 
Just need more roots in the solution. Have you been top watering at all?
Yes at first. Maybe too little tho. This could be a reason that they grow so bad but since the roots are in the water it shouldn't be necesarry anymore right? Next time I will add a drip ring with a timer and let it flush one to two times a day for about 15 minutes until a root base has formed, I am just a little scared that the rock wool soaks too much when I do that but I think the hydroton dries quickly.
 

terpedup83

Well-Known Member
doubt it, could be the beans, some beans are bad, pop some more while you try to figure this out so the ball is already rolling if you trash these ones
 

Boatguy

Well-Known Member
Yes at first. Maybe too little tho. This could be a reason that they grow so bad but since the roots are in the water it shouldn't be necesarry anymore right? Next time I will add a drip ring with a timer and let it flush one to two times a day for about 15 minutes until a root base has formed, I am just a little scared that the rock wool soaks too much when I do that but I think the hydroton dries quickly.
That is still a very small root system. A drip ring would help speed growth till you had enough roots in the res.
I wouldnt consider starting over here at all. Learn from your mistakes, and finish out the grow.
 

terpedup83

Well-Known Member
if it was a photo i would agree with the previous post but its a auto and the clock keeps ticking its gonna be flowering in 2-3 weeks
 

Johiem

Well-Known Member
Those time frames are just a guideline sounds like you're expecting nature to be clockwork. Surprise! She's not. Keep them rolling, you can see that they're not doing too much above ground, but look at what she's been doing below the surface. As long as those roots stay healthy, let them do their thing. As "Growers" we're actually more like butlers and nannies to the plants.

And with autos, you're just along for the ride
 
Thanks for all your replies. I will keep them alive at least until Saturday. I don't have new seeds yet, and maybe I will keep them and take it as a learning run.

if it was a photo i would agree with the previous post but its a auto and the clock keeps ticking its gonna be flowering in 2-3 weeks
Yea, I am not sure about the whole thing either. I have no experience with autos, so I am not quite sure if they will just flower a little later because they went through tough times or if they just give me tiny baby flowers (which I am certainly not looking for).

Those time frames are just a guideline, sounds like you're expecting nature to be clockwork. Surprise! She's not. Keep them rolling, you can see that they're not doing too much above ground, but look at what she's been doing below the surface. As long as those roots stay healthy, let them do their thing. As "Growers" we're actually more like butlers and nannies to the plants.

And with autos, you're just along for the ride
Do you know if autos are able to recover from early stress, or is it more or less a gamble?

Numbers:
I upped the ppm to about 300, added a little water so that the area below the netpot is more humid, and adjusted the pH to 5.7-5.8. The water temperature is around 68-71 °F. I add about 1 ppm of sodium hypochlorite every 3–4 days to prevent root rot. I don't use that much since my water temperatures are fine. Air temps are around 75 °F with a humidity of 55-60%.

Today was the first time I could see some progression since they went into the DWC system. They grew a little root mass and also don't look as sad as they did before. They still have weird discoloring which is probably caused by the stress they had during transplantation because I had no drip rings which resulted in dry hydroton (I was top feeding but probably not enough). They are also still very, very small, but I have seen some growth since yesterday.

I do not have drip rings, but I do own a 3D-printer and can print some, but I am not sure if this is still useful for this grow. In the next grow, I surely will use drip rings before even considering turning on the whole system. How many times a day should I run drip rings in a DWC system and for how long? Could you share your experience?

I printed some light covers for the pots, since my pots are 3D printed as well and out of white PLA.

I was also thinking about buying new fertilizer since mine is not 2 years old but more like 6–7 years. I have read online that they have no real expiration date, so I am not sure if I should just keep using them, since I don't want to waste anything.
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So the leaves are growing very slowly, the roots are not growing at all at the moment. I don't know if the water level is too high, but they still have like 2 inches space to the water. I increased the ppm to 400 with 1:1:1 ratio of T.A. (GHE) micro, grow, bloom in that order, pH is at 5.9, water temps at 70 °F. Humidity at 60+% and air temp at 74 °F.

I also decreased the light intensity since they are growing very packed, even tho they are not growing very fast.

Right now I have some guesses what could be the problem. They are sorted by probability, which I think could be a reason.

  1. I am using DanKlorix (European alternative for Clorox) for keeping the nutrient solution sterile and I only use a very small amount, but I have checked the ingredients and this raise some suspicion. It has besides Sodium Hypochlorite (2.5-3%) also Sodium Carbonate (1-10%). I have this information from the safety sheet. It also has Sodium Hydroxide, Potassium Iodide and Iodine, but in very small doses. Since I don't know if they harm the plant, this could be a reason the roots are not growing. I will not add the bleach for the next days, but I hope my solution doesn't go bad. I want to see if this could be a problem, there are some people tho who said they used it successfully which would speak against that theory and also as I said I only added a very small amount.
  2. My water level is too high.
  3. My fertilizer has gone bad.
  4. My nutrient concentration is too low.
  5. My air pump is too strong.
  6. The 420FastBuds automatic seeds are very bad.
  7. My light is too strong.
  8. A combination of all of the above.
 
Well, funny that you ask today. They did fine after I upped the nutes to 0.9 EC and grew very fast but I got root rot and gave them a chlorine bath two days ago. They did not survive that, maybe the strength was too high 20-30 ppm but I also had to cut some roots away so this could have killed them as well. In another forum someone told me to not use bleach as a preventitive, well..., from now on I will. I also will change the reservoir weekly which I didn't. I am just a little worried for my next plants since the weather is getting warmer and I think my reservoir could reach temps of around 80 °F which some people still manage without getting root rot. I will frequently change my reservoir, will use bleach or some other fungizid but I have to make research because where I live there is no Southern AG or Hydroguard, but I either go full sterile or full the other way. Sadly, a cooler is not in the budget right now and also they need a lot of power which went up in price tremendously. I will start my next round probably on the next weekend. I did learn a lot though.
 
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