HELP, ASAP! Babysitting dying plants

[Anemone]

So my friend has left the country for a month and hasn't really done his homework in regards to hydroponics and has built a shitty closet grow... I've been researching desperately in attempt to fix the plants he left which already had begun to dry up several days ago, now I need help to determine the problem(s) which i suspect many...

heres a pic of it 2 days ago...



Its Deep Water Culture with approx 8 gallons per tub, he had been changing the water out every 3-4 weeks, thinking flushing shocks the plants, i have begun flushing after they hit the 2 week margin and plan to do it weekly.. its in possibly the 3rd or fourth week of flowering

hes had the ppm's around 1130, using GH 3 part solution, ive got it currently around 900. The water I used is 3/4 tap water, left to sit overnight/RO water
theres only like 6 cfl's all 23W for 4 plants
he also has pet store airstones split between a fusion 500 air pump that has a lowly output of 3.4 l/m

I first believed the pH has been kept too high, he had told me to shoot for 6.5, so I had it around there (pH testing drops) for 2 days, then read some/switched to around 5.8. He says he had been keeping it around 6-5.8, but I'm not too certain as he's quite the stoner..

the closet also has poor ventilation, only the cracks in the door, plus a dual fan pointed at the middle of the door

also the tanks allow light to enter, while i dont see visible algae, its a possibility..



The leaves first turned yellow, then brown/spotty and curling upwards, signs of nutrient deficiency or burn..? My best guess is deficiency due to pH fluctuation and lack of oxygenated water

what do you guys think?

 

[Hushpuppy]

You are correct that there are several issues happening there. First and foremost is the lack of ventilation as those plants look heat cooked. I would be willing to bet the lights-on temps are running in the upper 80f to low 90f. And it wouldn't suprise me to find that the res water is also above 80f. That is the main problem.

The PH being around 6.5 will not typically do that, but it will cause the plants to yellow-off early as it is too high for hydro. It should be checked regularly and you should see a fluxuation between 5.3-6.2. Some people(and plant strains) are capable of maintaining a more stable ballance of PH around 5.8(which is ideal for hydro) Some will find that their PH will begin low and drift high, while others like myself have to start high(6.2) and let it drift low for several days before resetting it.

You don't necessarily have to replace the water every week but you would have to correct the PH every few days if you don't. I only replace my water in my res 3x throughout the grow, but I adjust my PH every other day, and I use 30gal res for 4 plants. If you are replacing the water in the res once a week then you don't have to worry about correcting the PH as much accept at initial replacement.

Depending on the strain of plants you have, you may need to run the ppm around 1300 during flower, or it may take less if it is a light feeder. I have some indica dominant plants that are quite happy at 1400ppm, then I have some that do great at 1000ppm. Given the state of those plants, its just as well that you cut the nutes back.

Those plants need some serious ventilation. Acouple of cracks and some fans blowing the air around is killing them. Tell your friend that if he think they don't, he needs to sit in that space with the door closed, under those lights for about 6hrs and see how he feels. Those plants are in that space for at least 12hrs without fresh air input. The only way to save any of the harvest is going to be to get fresh air in there continually so that the temps can be kept around 75f, and the water around 68f.

What you need to do at this point is take scissors and a vacuume and go remove all of the dead leaves and any that are more than 50% dead, so that the living can get the light that it needs, then get a way for fresh air to be continually cycled through that space.

Oh yeah, the lack of oxygenated water is probably not THEE issue but it certainly is AN issue. With DWC, The more bubbles the better. You want to see that water nearly boiling with air bubbles.

If you need any help with ideas or explanations don't be afraid to ask

 

[Dr. Green Fang]

Sure is a sad sight but that bud actually looks alright, so should be able to bounce back is my (noob) guess. Man.. they are surely cooked!

 

[4u2sm0ke]

Theres no hope for those..best to tear down and restart and run them correct..Salvage what ya can ....IMO..would clean house

:48:

 

[The Hemp Goddess]

I agree that those are probably goners.

There is so much wrong with this grow that it is probably going to be impossible to nail down one cause--poor oxygenation of the res, too high of pH, transparent res containers, not changing out the res often enough, inadequate light, and no ventilation probably all contributed to what you see now. I do have to say that I am a little surprise that your buddy even got them that far.

 

[DDragon]

I agree with everyone here,tear down and start over...correctly!






The only thing I see right about this grow is they do appear to be MJ, LOL!


Surprised they made it this far, too bad too...must have been a strong strain!