Drooping after transplant from DWC to NFT

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Hi all,

I moved seedlings from a DWC pre veg box to an NFT-ish system (aeroflo-like, see https://www.rollitup.org/hydroponics-aeroponics/611163-tight-space-hydroponics-setup.html ) after they had sufficient roots (over 8" in length) and now they are starting to droop/hang a bit.

First day just the larger one, seemed to go fine except that temps in the rez rose to 84 degrees over night. Strangely it didn't effect the plant noticeably. Turned of light and removed a pump that heated things more than it was supposed to cool through a diy chiller, cooled the rez (fairly slowly with frozen bottles of water), and added the second seedling (the one on the left).

Second day, they both droop, while the rez temp is fairly stable at 64-68. Raised the tray a bit on the lower end. Added air pump to rez. The pump itself is next to the active air intake of my grow closet, which keeps the rez temp at 64.4 degrees, and ridiculously stable too. Drooping seemed to be a little less, but I had also sprayed some H&G Magic Green on them which may have contributed to that (so should not have done that to prevent the skewed view on it).

Third day (is last night), added the third plant (on the right in pic). Didn't start drooping as fast as the other small one, looks like it will eventually though if I don't solve the actual problem.

47.jpg

I wasn't planning on adding the air pump (two waterfalls...) but the drooping reminds me a lot of drowning plants on soil so I figured I should try and raise the DO. That's why I added the airpump + bubble stone, which has the major added benefit of keeping the rez cool.

PH is 5.6-6.2 (mostly 5.7-5.9), ppm is 600. I know the PPM is low, but already had nuteburn last week on the smaller ones so talking it slowly. Can/should I use more in an NFT than in DWC?

While designing my diy setup and reading up on similar systems I noticed someone flood the pipes by adding a dam to the end, basically raise the water level in the trays. Something I built in as an option in my system but rather not go there just yet.

Things I can try:
1. clean the rez, again. Just cleaned thoroughly days ago before adding the plants. Ran plantless for about a day. Reason to clean would be to exclude pollution (from whatever-- like it being new).
2. lower the pump throughput (it's roughly 360GPH at max now). Since they look drowned I feel the need to give less water but it honestly doesn't sound like the solution (maybe on the contrary)
3. Raise the temp... I need to measure the temp of the returning water to see what the roots actually get, if the sprayers cool it too, they might just have cold feet.
4. Put the pump on a timer, like shut it down for 10 min every two hours or so (pump is currently 24/7 as suggested by others)

Any suggestions/ideas? Or is it not uncommon for them to droop and slow down after moving from DWC to NFT. They went like Turbo in the DWC (TL lamps). I've had one very successful run on soil in my grow closet, during the colder-than-now winter months so I think the problem is with(in) the system and not the environment. They are currently under 400watt HPS (like usual for me during this stage).
 
sounds like maybe they were used to be submerged in water, now they arent. they are angry and confused. raise the level of the water in the nft. or maybe just lower the neut level and give thema week to get happy again at the current hieght and go from there.
 
These two pieces are at the lower end of the tray, I can rotate the small hole in the pic below upwards to a point where the water level in the pipes will be at the same as they were in the DWC, i.o.w. right below the net cups.
48.jpg

I could lower it a bit every day or two so they can adjust. However, the thing with that is that I read a hydroponics blog from a grower who built several system and ended up running the trays at that high water level as it overall got the best results. Making me wonder, why would I lower it again if that makes them happy...

Thanks for the replies, I'll give it shot. It would put them back in a similar environment as the DWC, so if they remain unhappy it has to be something else.

There are two ways I can test it though, because I have two trays. I have another seedling ready to be moved, a stronger strain as well, I could place it in the other tray, raise the water level in that one only, and see if it starts drooping or not. That would prevent the other from going back and forth possibly causing more stress. Lights are out for the next 2.5 hours so still have a little time to consider :)
 
I just raised the lower end of the pipes/trays and that raises the water level about 1/4". Will transplant another one later today, hopefully it will still look ok tomorrow. The larger one drooping less gives me the impression that she can handle the amount of water and the small ones should actually get less but guess that's from coming from soil as well.

Would watering from the top a couple of times a day help smoothen the transition?

Edit: just took the time and effort to turn that offset pvc adapter, raised level to 1/3" below the net cups.
 
Looks like the low water level was the problem indeed. Besides turning that offset hole in the pic above I raised both trays to be horizontal. Filled the other tray last night and they still look happy. The droopy ones clearly look better after one night already. Guess I'm running an NFT-Aero-SWC hybrid now... ah well, who cares about the semantics, I hope they pick up the same speed again as they had in the DWC.

Thanks again.
 
The larger size is what we have in homes for toilet sewer, the smaller hole is 4cm which is the common size used for sink/show drains etc. So it's basically an adapter.

I do have to pull it out before I can turn it, but it indeed seals 100% without glue/putty/tape. I got most of it from a sort of (local to Netherlands indeed) online PVC outlet but they are at any home improvement store here. I got some pieces glued, without the rubber, on the other ends as well cause it's about 50% more expensive for the same piece.
 
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