Sudden death of first plant in RDWC, water level too high?

poindexterous

Active Member
Sorry I don't have a pic of the plant, but here's one of my first "trainer" single place RDWC. What happened isn't hard to visualize though.

I put a well rooted clone in this setup and at first it worked great, plant quickly grew to a small bush, just wider than the bucket and about as tall, was one of the best looking plants I've grown. Then one morning I found it totally dead, fully wilted and collapsed, went from perfect to toast in less than 12 hrs? Water conditions never changed, power never went out, temps normal.

I heard I was supposed to lower the water level to below the net pot/hydroton once roots came through the, but hadn't yet, putting it off I guess, it was still bubbling half way up through the hydroton. So I'm assuming that was my error? There was some whitish slime on the main stem within the root mass, though the lower roots looked good. Is my diagnosis plausible? Does everyone lower the water level after a while? Thanks!

IMG_2170.JPG
 

Shafto

Active Member
If you water level was really high and you has less than ideal dissolved oxygen, or maybe a res too small for you plant, you could get stem rot and kill it slowely, but not overnight.

I honestly don't know what could have done that other than some type of serious over-nute or poisoning of some kind.

I experimented with my water levels for a bit and found that 1 inch of my 8" round netpot submerged works best for me. I tried with it bellow for a while and you just get those twisted lumps of corded up roots that don't do anything but support the roots bellow. They don't feed on anything. I tried that at first cause I had read about the air gap being kind of like an aeroponic zone for the roots to feed in a different way, but that's not what happens, you don't get any of those fine fuzzy roots like aeroponics, just clumped up twisted thick gnarly roots that are only for support.

With the bottom of the pot just submerged, you get more res area for more nutrients in total to feed on, and also create more area for feeding rootmass to grow. I've never had a problem with any kind of rot. Aeration and water circulation are key. Adding a separate reservoir with a pump to circulate into the grow bucket will help immensely. The easiest way to do it is to just top off your grow bucket with a pump, and then drill a hole in the grow bucket where you want the water level to stay, then put a drain tube there back to the feeding res with the pump in it. Feeding res must be lower than grow bucket by a few inches for it to drain back properly. This way your water level in grow bucket is always the same, and it only drops in your feed res. Adding more total water volume to hold more nutrients is a huge help. More water volume takes a lot longer to get mucked up.
 

poindexterous

Active Member
ouch. sorry man :\
Thanks. It was a test so I don't mind the loss if I learn from it, better one than many. Once I get it down then I'll build a multi-bucket system. Just started it back up with a new clone so hopefully this one will do better.....
 

asaph

Well-Known Member
yeah but like shafto here said, it's really quite impossible that the water level was the cause of this. must have been something else. can you think of anything?
 

poindexterous

Active Member
If you water level was really high and you has less than ideal dissolved oxygen, or maybe a res too small for you plant, you could get stem rot and kill it slowely, but not overnight.

I honestly don't know what could have done that other than some type of serious over-nute or poisoning of some kind.

I experimented with my water levels for a bit and found that 1 inch of my 8" round netpot submerged works best for me. I tried with it bellow for a while and you just get those twisted lumps of corded up roots that don't do anything but support the roots bellow. They don't feed on anything. I tried that at first cause I had read about the air gap being kind of like an aeroponic zone for the roots to feed in a different way, but that's not what happens, you don't get any of those fine fuzzy roots like aeroponics, just clumped up twisted thick gnarly roots that are only for support.

With the bottom of the pot just submerged, you get more res area for more nutrients in total to feed on, and also create more area for feeding rootmass to grow. I've never had a problem with any kind of rot. Aeration and water circulation are key. Adding a separate reservoir with a pump to circulate into the grow bucket will help immensely. The easiest way to do it is to just top off your grow bucket with a pump, and then drill a hole in the grow bucket where you want the water level to stay, then put a drain tube there back to the feeding res with the pump in it. Feeding res must be lower than grow bucket by a few inches for it to drain back properly. This way your water level in grow bucket is always the same, and it only drops in your feed res. Adding more total water volume to hold more nutrients is a huge help. More water volume takes a lot longer to get mucked up.
Funny thing was nothing changed in the water from the previous week that it was doing great and growing fast. So are you finishing your plants right to harvest with the water 1" into the netpot, and that's been smooth sailing? Mine was closer to 1" from the top. Maybe that makes the difference?
 

poindexterous

Active Member
yeah but like shafto here said, it's really quite impossible that the water level was the cause of this. must have been something else. can you think of anything?
Hmmm....nothing that day. 4 days earlier I had moved it from T-5 light to MH but it seemed to love that. perhaps the water temp rose under the MH and a pathogen broke out suddenly?
 

woodsmaneh!

Well-Known Member
Was the plant wilted and laying over on it's side? Lack of 50 to 60% humidity will do that.

The last 2 weeks for flower if different, make sure the humility is dropped as low as you can get it, for me 30% this will increase resin production.

Water level should be just over the net pot by about an inch. I run a dripper tube the first week to 10 days than turn it off, When roots start to push through the bottom of the pot drop to 1 inch away from the pot. 4 weeks later drop another inch than during the final 10 days drop the level by 1/3 to 1/2, this will help stimulate the plant and increase resin production. You can see it in the picture, there turned off as the plant is 3 weeks old. :blsmoke:

View attachment 1633173
 

poindexterous

Active Member
Was the plant wilted and laying over on it's side? Lack of 50 to 60% humidity will do that.

The last 2 weeks for flower if different, make sure the humility is dropped as low as you can get it, for me 30% this will increase resin production.

Water level should be just over the net pot by about an inch. I run a dripper tube the first week to 10 days than turn it off, When roots start to push through the bottom of the pot drop to 1 inch away from the pot. 4 weeks later drop another inch than during the final 10 days drop the level by 1/3 to 1/2, this will help stimulate the plant and increase resin production. You can see it in the picture, there turned off as the plant is 3 weeks old. :blsmoke:
Nice photo, happy plants!

No, my humidity stays around 50%, plus all other non-rdwc plants in room are fine. Had to be in the root zone.
 

Shafto

Active Member
Temp increase could have caused a pathogen outbreak for sure. Never seen one die so fast but I suppose it's completely possible. I run 1 inch above bottom of netpots for the whole grow. I don't put clones in until they're roots are long enough to poke through the bottom of the net pot, so no need to have it any higher.

The increased resin production from making the plant think things are getting drier might work in some cases, like soil where you can dry out the entire root zone, but I didn't see any difference in DWC when I tried it. I noticed the plants responding badly, and not liking the loss of feeding roots now stranded in the open air when the plant needs to feed the most.







 

poindexterous

Active Member
Temp increase could have caused a pathogen outbreak for sure. Never seen one die so fast but I suppose it's completely possible. I run 1 inch above bottom of netpots for the whole grow. I don't put clones in until they're roots are long enough to poke through the bottom of the net pot, so no need to have it any higher.

The increased resin production from making the plant think things are getting drier might work in some cases, like soil where you can dry out the entire root zone, but I didn't see any difference in DWC when I tried it. I noticed the plants responding badly, and not liking the loss of feeding roots now stranded in the open air when the plant needs to feed the most.
Nice setup, and nice looking root mass! What temp are you keeping the water? And while I'm asking, what pH and ppm?

Your system makes me hesitate to believe that my water just being a couple inches higher did it in. I hadn't considered temp till it occurred to me in this thread. Either way a pathogen seem the only plausible answer so far. Thanks for the pictures, very helpful to see other setups.
 

Shafto

Active Member
Thanks.

I keep the water around 66-67. PH I keep between 5.5 and 6. As for PPM, I couldn't tell you exactly, I use technaflora nutes, and I just mix them as per their recipe, then add back straight water and change out the whole res every week. I slowly let the level in the feed res drop through the week to keep what I feel are stablish PPMs based on the plant's response. I have been meaning to get myself a PPM meter though, if only to be more conservative with my nutrients, doing add backs with nutrients and maybe changing out the whole res every 2 or 3 weeks.
 
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