Seedling DWC Problem

guitarguy10

Well-Known Member
I moved seedlings in rockwool to DWC 4 day's ago and their growth has been stunted and they are going yellow and burnt tips as in this pic:

They are under just 2 60w CFL bulbs, temp is about 20C, RH about 50%. Giving them tap water with Sensi Grow A and B enough that the EC is 0.7and pH is 5.9. They are in 12 gallon bins 2 plants per bin.

I had the water level pretty high but then just decided to topfeed them for now so that I am certain they are getting fed, so I have been giving the rockwool a little bit of water maybe once a day.

I still need to cut off that plastic around them they are just so fragile right now that I don't really want to touch them I would probably end up killing one.
 

guitarguy10

Well-Known Member
0.7 is pretty high IMO unless your tap is high.

I personally hate RW. it's either too wet or too dry. try Rapid Rooters instead next time.
0.7EC = 350ppm (x500 conversion)

My tapwater is over 200ppm. I've tried rapid rooters, they sucked for me too lol, they dried out about as fast as rockwool has been, in any event i don't think that could be a problem since they are in pots with clay pebbles now.
 

rkymtnman

Well-Known Member
Yeah, i know the conversion. I just finished a run and my max EC was 0.7 with 0.2 well. I feed once a day in drain to waste.

If I were you, I'd get RO water (either buy it or buy a RO unit), cut back on your nute EC and add cal/mag.
 

Airwalker16

Well-Known Member
If you don't have roots dangling into the water below the net pot, this is exactly what you can expect. You need to hand water it everyday, or keep them In a very humid area, 75%+ and suspend the cube in the air to let the roots grow out and down from the rock wool, so that when you do transfer to a net pot filled with hydroton, you have some roots to work through the net pot that can be in the water.
150ppm is more suited for that size. 300-350 is around 6-10" tall.
 

Wastei

Well-Known Member
I think you have to lower the water level to 2 inches below the netpots and hand feed til you see some roots reach water level. They are probably suffocating from lack of oxygen, standing in stagnant water.

You can save the situation by not overwater the rockwool cube. Think of ways to avoid this. Good luck!
 
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Logan Burke

Well-Known Member
Even if your tap is roughly 200ppm, I'd still be hesitant to add nutrients at all until the seedling drops it's roots out of the netpot. This is usually when I add nutes, and even then, I start low. Just a tip for future reference...I've begun using a method for DWC seedlings that totally removes the step of using RW or root plugs. I germinate seedlings in a paper towel, allow the tap root to grow at least an inch, and then place the seedlings into neoprene inserts that one would use for clones. I then place the neoprene inserts into my DIY aerocloner, so that the tip of the tap root is at least barely sticking out of the bottom of the neoprene and gets misted constantly by the sprayer underneath. After the main tap root grows to an overall 3-5 inches in length, I then take the seedling out of the aerocloner and dangle it over an empty netpot. Next, I slip the tap root in between one of the slits in the bottom of the netpot, and CAREFULLY and SLOWLY begin to fill in the netpot with hydroton with one hand, while holding the seedling upright in the other. I slowly fill in the hydroton ensuring that it doesn't scrape or rip the baby roots, and fill it in until I'm happy with how much the seedling is sticking out and is being well held by the hydroton. This way, you get instant roots in the water and get to avoid ANY type of RW, root plug, or other medium but for hydroton.
 

Logan Burke

Well-Known Member
I also forgot to mention, you are covering the RW up with plastic it would appear and if that is the case, excess water will have an even more difficult time evaporating and escaping the RW.
 

myke

Well-Known Member
This^ cut the plastic back so net pot is exsposed,water just below net pot.bubbles splash the first layer of pebbles,roots will find the water.be patient.good luck.and ya your ppm is good.
 

guitarguy10

Well-Known Member
I am taking the ppm down right now, and I've cut the plastic off to expose the net pots.

I'll take that idea into consideration exposing the roots in the future but I think I will probably end up going back to coco cuz this is just to .... uh, wet lol.
 

Logan Burke

Well-Known Member
I am taking the ppm down right now, and I've cut the plastic off to expose the net pots.

I'll take that idea into consideration exposing the roots in the future but I think I will probably end up going back to coco cuz this is just to .... uh, wet lol.
Yeah that is exactly why I chose to bypass rockwhool and rooter plugs altogether. I'd just cut back on how often you're applying water and you should be ok...they'll dry out if allowed too. If it's still staying saturated just from the water bubbling underneath, then drop the water level until it gets to where it isn't keeping the RW soaked. There are a thousand and one ways to do this process...I wouldn't give up on hydro yet, the hardest part of hydro is finding your groove, or your routine. As long as it works for you, then it works!
 

fragileassassin

Well-Known Member
The seedling transition seems to be the weird part of dwc. I've recently been playing with ways to make this smoother and faster by getting seedlings into a small bubble bucket or the cloner as soon as they are big enough for the collars. They seem to take off much faster than I was experiencing in trays. Transplanting into the larger system only when the roots will reach out of the bottom of the net pots a couple inches has made for very easy transplants for me. I cut small holes in the bottom of the net pot to feed the roots through then gently fill in around the root.
Have another set of seeds I dropped yesterday and plan to play with this some and share results.
 

Airwalker16

Well-Known Member
The seedling transition seems to be the weird part of dwc. I've recently been playing with ways to make this smoother and faster by getting seedlings into a small bubble bucket or the cloner as soon as they are big enough for the collars. They seem to take off much faster than I was experiencing in trays. Transplanting into the larger system only when the roots will reach out of the bottom of the net pots a couple inches has made for very easy transplants for me. I cut small holes in the bottom of the net pot to feed the roots through then gently fill in around the root.
Have another set of seeds I dropped yesterday and plan to play with this some and share results.
Yup, just gotta snip out one piece off the netpot bottom. Gives about a 3/8" hole for the roots to go though. Static/water tension can be annoying sometimes trying to get it through there though. Haha
 

fragileassassin

Well-Known Member
Yup, just gotta snip out one piece off the netpot bottom. Gives about a 3/8" hole for the roots to go though. Static/water tension can be annoying sometimes trying to get it through there though. Haha
I have the benefit of an extra set of hands when it comes to important stuff like transplants. Makes that part much easier.
I was a bit surprised at what time in the little cloner like bubble bucket did with some nearly dead tiny seedlings. Getting them into a smaller hydro system as soon as possible is going well so far.
 

guitarguy10

Well-Known Member
How do they look?
They still look pretty bad, but I'm just going to leave them and be patient. I went and bought enough distilled water to bring their EC down to about 150ppm, the plastic is gone and i lowered the water level to like an inch or 2 below the net pots. I will try and add pics later but they don't look much different then they did in the first pics I posted, we'll see though I havnt had a chance to check them today (lights just came on).
 

myke

Well-Known Member
Ya gots lots of air bubbles? The bottom of net pot should drip a little from the splash.
 
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