Hydro.... DWC - Keep Rockwool WET or DRY???
- Thread starter pftek
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milehighmedical
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chunky_nugs
New member
You want to keep the Rockwool moist. Hand water them daily.
I do DWC, the drip feeder first goes into my rockwool, so they are getting wet everyday.
Second, I have a bit of a gap between my water level and the "air" has never stopped any root growth. They will grow plenty out of water.
Some DWC I know flood and drain almost and allow the roots to grow huge in those buckets.
Make ssure you have air pumps or you will drown your rots.
I do DWC, the drip feeder first goes into my rockwool, so they are getting wet everyday.
Second, I have a bit of a gap between my water level and the "air" has never stopped any root growth. They will grow plenty out of water.
Some DWC I know flood and drain almost and allow the roots to grow huge in those buckets.
Make ssure you have air pumps or you will drown your rots.
Plant a seedling or clone too low and growth will stall for 2-3 weeks as the plant grows roots towards the surface in search of air. Some non mj plants are so air hungry, they grow these roots above ground.
The point of DWC is maximizing air to the roots, esp the upper ones. This is why DWC outgrows soil, why aero outgrows DWC and why foggers outgrow aero. A large block, or netpot, of Rockwool minimizes air to the roots, it defeats the purpose of DWC. As long as your water is aerated, you should be OK but, no matter how aerated the water is, air will have more available O2 than water.
You need no solid media for DWC. Netcups simply keep the plant from falling into the tub. Starter cubes (jiffy cubes, peat pellets) are a convenience used to start seeds or clones because, as the plant grows larger than the cube, the cube is ripped to shreds.
If roots are long enough to span a gap, provide the gap. If not, maintain direct water contact until they are long enough to span the gap. The gap is where the magic happens.
The point of DWC is maximizing air to the roots, esp the upper ones. This is why DWC outgrows soil, why aero outgrows DWC and why foggers outgrow aero. A large block, or netpot, of Rockwool minimizes air to the roots, it defeats the purpose of DWC. As long as your water is aerated, you should be OK but, no matter how aerated the water is, air will have more available O2 than water.
You need no solid media for DWC. Netcups simply keep the plant from falling into the tub. Starter cubes (jiffy cubes, peat pellets) are a convenience used to start seeds or clones because, as the plant grows larger than the cube, the cube is ripped to shreds.
If roots are long enough to span a gap, provide the gap. If not, maintain direct water contact until they are long enough to span the gap. The gap is where the magic happens.
pftek
Member
Plant a seedling or clone too low and growth will stall for 2-3 weeks as the plant grows roots towards the surface in search of air. Some non mj plants are so air hungry, they grow these roots above ground.
The point of DWC is maximizing air to the roots, esp the upper ones. This is why DWC outgrows soil, why aero outgrows DWC and why foggers outgrow aero. A large block, or netpot, of Rockwool minimizes air to the roots, it defeats the purpose of DWC. As long as your water is aerated, you should be OK but, no matter how aerated the water is, air will have more available O2 than water.
You need no solid media for DWC. Netcups simply keep the plant from falling into the tub. Starter cubes (jiffy cubes, peat pellets) are a convenience used to start seeds or clones because, as the plant grows larger than the cube, the cube is ripped to shreds.
If roots are long enough to span a gap, provide the gap. If not, maintain direct water contact until they are long enough to span the gap. The gap is where the magic happens.
The problem with submerging the rockwool is the plant ends up getting moldy and dying. Usually black shit appears on the rockwool.
Does having lots of air really make a difference or is this just theory? Cause I've tried lots and lots of bubbles to just a few here and there. After the roots have formed from clones... I haven't noticed a difference. As long as a piece of the root has O2 wouldn't the whole root and plant have O2??
That's why people avoid large Rockwool blocks in DWC. Because it wicks, it's always saturated. Hydroton doesn't wick. It will adsorb to a degree but water can and will fall out while the much larger air gaps in the cup allow breathing.
Air is everything. Again, it's why DWC outgrows soil, why aero outgrows DWC and why foggers outgrow aero. Unfortunately the "higher" up the technical chain you go, the greater chance of catastrophic failure.
once ya got roots theres no need to water the rw cube they uptake nutes through the rootes in the water. i get green shit on the top sometimes but it never killed nething i guess i would be more concerned if it effected the plants but it is scary to see if ur not used to it.lol best of luck
FB- love that drawing expains everything without a word...
FB- love that drawing expains everything without a word...
chunky_nugs
New member
i only use a 1 inch Rw and Hyrdoton.
Drains better, less salt build up and less ph change.
Drains better, less salt build up and less ph change.
evergreen
Member
@ freezerboy: and what would you recommend, keeping the rockwool cubes wet or let them dry?
2 quite different opinions...
i let the rockwool cubes dry, cause im afraid of mold, if i handwater them every week...
i guess the root-growing question of the thread starter isnt that important as long as the roots are growing, but would be one benfit of keeping the rockwool cubes wet... more rootgrowth... but will it mold, and possibly cause root rot?
Without pictures, we don't really know what's being discussed. I'm talking blind here.
If you're using a large cube jammed in a netpot, or a netpot full of starter cubes and/or plugs I think you have to keep it wet. One, because while they need air, the upper roots need to be moist. Two, because rockwool* wicks. Any water bubbles that hit it from below will get sucked in and travel up to the top of the cube. It's unavoidable.
This time around, just make sure the water is heavily aerated. I use a 60 gal pump for my 12 gal tub and a 10 gal pump for my 2 gal cloner.
FWIW my first successful DWC test run was with a 4" Rockwool cube jammed in the top of a DWC bucket. Worked great until the plant went hermie (unrelated to grow method, just bad seeds) Still, it went about 7-8 weeks altogether. Doing a SOG type grow, I'd think you'd want to minimize veg time anyway (again, talking blind here, our views of SOG may vary) A fast flowering strain would only take another week or three to finish. Punchline being, I think you can pull this off though, I'd avoid it in the future in favor of Hydroton or no media at all.
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If roots are long enough to span a gap, provide the gap. If not, maintain direct water contact until they are long enough to span the gap. The gap is where the magic happens.
FB, thanks for being such a steady source of information.
I've been doing the DWC for years now but still need to learn a thing or nine. What is your thinking behind the gap? I ask because Heath Robinson says that a gap contributes to cord roots which he doesn't like.
I'm having some trouble with sudden death in some test methods and I'm wondering if I am drowning the plants. How does the water level / air to the roots relate to stem rot / drowning in your opinion?
Thanks,
evergreen
Member
thats really what im thinking about. my current setup are large rockwool cubes jammed into netpot. but if it doesnt touch the waterline, the rockwool will dry up and stay dry, no wicking...
the question is what is better/healthier for the plant/roots, let the rockwool stay dry, or handwater to keep them wet...
do the upper roots realy need to be moist? roots which stick out of the ground in soil-growing turn woody and hard...
FB, thanks for being such a steady source of information.
I've been doing the DWC for years now but still need to learn a thing or nine. What is your thinking behind the gap? I ask because Heath Robinson says that a gap contributes to cord roots which he doesn't like.
I'm having some trouble with sudden death in some test methods and I'm wondering if I am drowning the plants. How does the water level / air to the roots relate to stem rot / drowning in your opinion?
Thanks,
Not familiar with Heath or "cord roots". Got a link?
I do a single plant ScrOG in an 18 gal tub (12 gal nutes). I top off every other week so, my gap drops to 4-6 inches...
The only sudden deaths I've had were from drying out in the seedling/new clone period (I transplant at the very moment I see sprouts or root tip. If I can't see the roots, I can't break them) I've found contact with netcup isn't always sufficient as hydroton doesn't wick. The starter cube can dry out and kill a seedling in less time than a good nights sleep. EEK! This is why I now maintain contact with the cube itself until there are roots long enough to span the gap.
As to your problem with stem rot, what media? DWC shows plants can live in water with sufficient aeration. What sort of aeration are we talking about?
Air stones will send water spray upwards several inches, maybe as much as a foot. With a standard 1" gap, your cubes have no choice but to remain saturated. To prevent this saturation, you'd have to increase the gap to 12 inches or more. Now you're getting into aero/fogger territory where roots live media free in a perpetual mist.
Lacking misters/foggers, such a large gap could be deadly. I'd live with the situation for the remainder of the grow, scraping off algae from the top of the cube to allow evaporation. As water evaporates from the top, it's absorbed at the bottom with oxygenated water.
Not familiar with Heath or "cord roots". Got a link?
I do a single plant ScrOG in an 18 gal tub (12 gal nutes). I top off every other week so, my gap drops to 4-6 inches...
The only sudden deaths I've had were from drying out in the seedling/new clone period (I transplant at the very moment I see sprouts or root tip. If I can't see the roots, I can't break them) I've found contact with netcup isn't always sufficient as hydroton doesn't wick. The starter cube can dry out and kill a seedling in less time than a good nights sleep. EEK! This is why I now maintain contact with the cube itself until there are roots long enough to span the gap.
As to your problem with stem rot, what media? DWC shows plants can live in water with sufficient aeration. What sort of aeration are we talking about?
Here is the link to the way I want to be. Heath is UK I think, but is world #1 for me.
https://www.icmag.com/ic/showthread.php?t=181239
The suden deaths I've had occur in systems that have 100% refill rates (via float valve) UCs and systems that are on floating net pots (rafts).
My supposition is that I was drowning the HUGE plants by depriving them of O2, and your suggestion that there is more in the air than water got me thinking.
So what I am really interested in is your thoughts behind the gap and gap fluctuation and optiminization of the plant.
Your photo looks great, but it doesn't display the chords that one would expect from a 1week period between fills. Perhaps the entire bucket was filled weekly. What was the low point of the water line normally? I think my deaths are from having the plant at 100% full 100% of the time.
tonsoffuns419
Member
would anyone be kind enough to also post a link or explain transplanting into larger net pots for dwc bucket grows.
really is dependent on the amount of roots comming out of the net pots, but you just turn the pot over holding the plants and drop them in the new bigger pot.
the thing your missing with heaths grows are he vegges for 8 weeks
a plant grown in dwc for 6 weeks veglooks like this now imagine the yield thats gonna bring when flowered
i only used the 1" rockwool starter cube as this is all you need and as long as you have enough oxygen flying around your buckets then your good to grow
i use a 60 ltr per minute pump and 2 x 20ltr buckets so i have supercharged the amount of o2 in the buckets
the rest is just your lights
a plant grown in dwc for 6 weeks veglooks like this now imagine the yield thats gonna bring when flowered
i only used the 1" rockwool starter cube as this is all you need and as long as you have enough oxygen flying around your buckets then your good to grow
i use a 60 ltr per minute pump and 2 x 20ltr buckets so i have supercharged the amount of o2 in the buckets
the rest is just your lights
Here is the link to the way I want to be. Heath is UK I think, but is world #1 for me.
https://www.icmag.com/ic/showthread.php?t=181239
The suden deaths I've had occur in systems that have 100% refill rates (via float valve) UCs and systems that are on floating net pots (rafts).
My supposition is that I was drowning the HUGE plants by depriving them of O2, and your suggestion that there is more in the air than water got me thinking.
So what I am really interested in is your thoughts behind the gap and gap fluctuation and optiminization of the plant.
Your photo looks great, but it doesn't display the chords that one would expect from a 1week period between fills. Perhaps the entire bucket was filled weekly. What was the low point of the water line normally? I think my deaths are from having the plant at 100% full 100% of the time.
Wow. That's some grow Heath's putting on, ain't it? Mad props, Heath! If I've misrepresented your position, set me straight, my apologies.
First, I have to say my top off methods are not based on maximizing plant needs as much as allowing plants to survive my lifestyle where business often takes me from home weeks at a time. I can go 2 weeks with no trouble. I can survive three but, plant's are royally pissed off when I do.
Note that Heath is doing dual tub waterfarms (top) as opposed to single tub "bubbleponic" style DWC(bottom).
Roots start big and then get small. We can't see inside the hydroton filled upper tub but, I wouldn't be surprised if there were "chord roots" up there.
Enlarge the first shot below and you can see the "woody" poking out to the right even with the bottom of the hood. Next is a closeup of said woody and then the larger rootmass
Here are my homemade netpot (BAD idea, don't do it) which seems to have more and larger "chord roots" However, it's a MUCH smaller pot. The roots are exposed to view much sooner. The closer you get to the stalk, the thicker roots will be...
Heath may not use an air gap below but, because it's a waterfarm, he has several inches of air above the lower tub. His gap is obscured by the opaque tub but, it's still there.
My thought is, within reason, the more air the better. That's why DWC outgrows soil, aero outgrows DWC and foggers outgrow aero. Air to the roots, esp the upper roots, is why they produce in the order they do. Unfortunately, each step up the tech ladder brings a greater possibility of immediate failure. Personally, I chose security over production. I can survive a pump failure longer than an aero/ fogger could. I won't have the total yield but, I'm overgrown as is anyway and I have a lower risk of coming home to dead plants.
