I'm Growing In An Nft 205gti ...all has been well for the first few weeks but im about 3 weeks into flower and the plants look like thier fighting an uphill battle with the tank .
ph is kept 5-6 and i keep them at ec 1.2-4. i turned down how many times they were watered a day as the matting looked waterlogged.
the plants don't have any deficiency symptoms , but they look wilted and the leaves look severely wrinkled like crepe paper. temps in area are 28 ish so iv run out of ideas any help much appreciated to save the chrimbo crop !! ty

Are the leaves curling down, like a claw?

Is the spreader mat in the water res, or above it? Sometimes, i've turned my pump off and let the plant just suck water up through the submerged spreader mat, which has remedied the problem.

How close is your lamp and what sort is it?

What are you using to adjust the pH?

How often are you emptying your tank and cleaning it out with fresh nutes?

Put a bigger tilt on the tray so it runs off quicker mate

If that doesnt help feed once every 2 hours or so, to see if that helps

Do a complete water change just to eliminate that as a problem

Owd

yeah they are curled down like claws. i have 600w hps about 3ft away. the spreader mat is long enough to reach into the res as i was told this was ok. ph down to control ph. usually clean the tank approx every 10 days.

Get a pic up mate as you said earlier that they were not deficient but you say they have clawing leaves

This could be too much N

If they are just droopy this will be overwatering

Owd

how big are your roots are they spreading over the mat? what temps are you getting at lights off? is your nute tank heated? are your roots covered?

Will Try a res change and might leave pump off for today and see if theres a change... night temps are good i dnt heat the res its usually lukewarm most of the day and night the house is well heated.
the roots are really going for it so i am at a loss. i did expect it was overwatering but as its nft i got a bit stuck as its always wet .
the plant nearest the pump is the worst off, looks lke its at deaths door. the one nearest the lip of the top tray were it flows into res looks ok tho.
the tank has been at an angle for the last week but only a slight improvement.
will res change ect and post tomoz if theres improvement. will leave pump off for a day aswell. ty guys

is the pump on full or just trickling

NFT systems are designed for a constant flow of water.....so the spreader mat should always be wet. Especially if the plants are established.
At three weeks in to flower, I don't think your problem is water related.


What is your air exchange like??

i think now u should put fresh water in there no nutrients for a week and see how they do then. maybe use some wilt gaurd and regen-a-root from canadian express?

i have a 100mm intake and an 125m outake both rvk.

sorted it all this morning. emptied the tank refreshed the res. there was a slight bit of brown gunk in the tank :S . cleaned it out and started again. then hours later checked the res.
there was a huge pile of salt looking sediment in it. just had to empty again. now discvered my light timer may be malfunctioning. im gonna ditch the nft and lay the mat across some rockwool. if these plants do make which i doubt, i have a feeling they will be very poor ones .
the timer was on to water all the time then i kept reducing it to 4 times a day. then twice. the plants didnt like being in the constant stream. i find nft quite demanding as i expected so i think i will stick to what i Know best which is rockwool slabs.
i feel that i may be too late to try the anti bacterial additives in the tank as the plants are seriously close to death ..

my wilmas like an nft, it recirculates just the same way but the roots are in pots.
x4 15 min feeds a day in flower is all they need if i gave them any more feeding they wont absorb any more water and wilt.
if i kept the pump on for 24 hour a day they wouldn't absorb any water i expect.

if your plants do not like NFT it is because you are giving them something in the water or system they do not like.

is there much oxygenation in the tank ? if your spreader goes all the way in the tank and you have no bubbler or pump, there will not be enough oxygen in the water, your tank solution should look clear and drinkable...

I still think it's overwatering. That's what i'd be looking at and i've seen it in my setup before. Especially if the plant most effected is near the outlet.

I'd just turn off your pump. It'll be fine for a few days or more than that - capilliary action will draw water up through the mat so your plants won't die. Just make sure the top of the mat highest isn't dry.

The roots will go to the water.

Clean fresh water, no additives, nothing. Don't pH it, just leave it. Get an airstone. Put it in your tank and pump air through it. Use your water pump to churn the water around; point the nozzle to the side and let it trickle back.

Get a water heater setup and monitor your temps to make sure they're ok. Throttle back the air if your fan can handle the heat lower. Basically, try and 'throttle down' the whole plant. Reduce stuff. With NFT, everything can be on a knife edge, you move either side of the optimum and you slide off. It doesn't help there are other knife edges such as light and air and nutes and temperature to balance on at the same time. Too much of anything by even a bit and the plant will suffer greatly. When you understand it, it's easy to balance it.

I've looked at a few commercial NFT systems, both tray, like my 205 tank and tube type systems. The tubes tend to have a very fast running flow of water, wheras those 205 tanks can get a bit of a soggy mat with slow movement, even 'pooling' when there are roots and cubes on top. Not great. Allow the mat to just take a break and acheive at balance is important I think and it differs depending on what material your mat is.

i have a 6 inch airstone on constant in the tank. iv turned off the pump and emptied the tank. they look a bit better today now the mat has dried a little bit. . would elevating the cubes slightly help ? im gonna water with plain water by hand for a few days and see how they go.