Just wondering if you can have a dwc setup run 18/6 or does it have to constantly run 24/7 ?
It needs to consistently run so the air pumps supply the roots with plenty of oxygen 
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Thanks man . That’s all I needed to know .
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Even if the roots have not touched the water yet ?
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Yes - for a couple of reasons. Bubbles and air form more humidity in the “gap” and also occasionally splash up onto the bottom of the net pot - this can sometimes be helpful in root production. And more importantly, oxidation in the the reservoir will help keep the water/solution stable. It also means that when your roots DO make it to the water, you won’t have to be there to make sure the pump is on. You should set it up as though it’s feeding from the reservoir IMHO.
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Air is delivered nonstop. If you are doing DWC there is no liquid pumping. RDWC you will circulate a few times per day to refresh the working solution and lower temps where applicable.
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Thanks for all the help you guys. So I should take some water out then if my net pot is about a inch into the water huh? First time here . Sorry for the boat load of questions .
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Generally you want a gap - 1" is probably fine - between the water line and the bottom of the net pot. I personally flood the crap out my net pots in my ebb and flow system, so I don’t really see any reason why you can’t get the hydroton wet, but generally accepted conventional wisdom on this front is that you should maintain an air gap - at least once the roots can make it down into the water at that level.
During the seedling stage, many DWC growers use a top feed ring to feed from above until the roots are long enough, and then they shut off the top feed ring. @TDubWilly uses one.
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Not anymore… now I leave the top feed running the entire grow 24/7. I had to make some adjustments to be able to do it but now I have highly oxygenated nutrient water dribbling down the roots and no damping off/stem rot.
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Anything that increases dissolved oxygen levels I leave running 24/7, so air and water pumps don’t ever stop running
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@TDubWilly This picture has me considering constant top feeding as well. Second generation roots from tdubs film experiment.
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The secret is to get the base of the stem and the hydroton as dark as possible.
When the stem is exposed to that much water and light at the same time it gets confused on whether it needs to turn to root or to stem, so for the hydroton to stay wet, it needs to be super dark
I actually have roots growing out of the stem above the hydroton then grow down into it
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The other great thing about this is it constantly flushes the hydroton and rockwool that can fester with nasties. This was a big !!! For me. I have constantly been plagued with early infections (damping off and algae in the net cup) that go away when the plant grows.
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I think you should reconfigure your system and try doing a grow using ebb and flow. Could you figure out a way to pump water in and out of your reservoir on a timer?
Flood from the top like you are with the ring, drain from the bottom back to a controller bucket of some sort…
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I will say this is the first grow that I incorporated this technique, so there was a period of time when it was young when the top feed was turned off and i didn’t have to battle with moist hydroton, this might have potentially been a good thing. If I ever come back to DWC I’ll try and do it the entire grow, but this grow the hydroton was dry when the plant was the most susceptible to root/stem rot.
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The main problem with the nasties I believe is the rockwool. It just holds way too much water and just rots! But when I actually flushed the rockwool/netcup when I saw symptoms it cleared the problem. Your top ring is a permanent solution. I just need to make it easy for swapping lids with my 5gal bucket system.
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Im sure I could… given space and electricity restrictions im trying to “build down” instead of “building up”, that’s why the next grow will be in autopots and this grow was in a one bucket instead of a two bucket system.
I will always feel as though hydro is the superior growth technique compared to soil. If I ever grow commercially I will never use soil. It just so happens my biggest need is just leaving the plant unattended for extended periods of time and those are the changes that I’m gonna make
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It’s funny you bring this up. With clones, I have been 100% successful at gently tearing off the rockwool before putting it into the hydro system but seeds are different.
The day I got talked into this the hydroton had been dry for several weeks. I gently moved the hydroton around the perimeter of the net pot and away from the rockwool and basically with no problem at all pulled all the rockwool off the stem and then turned the top feed back on, so there definitely is a need to eliminate the rockwool if your gonna do this
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