Experts opinion needed... offgassing room or nute shed. fail

[smailer]

Hello!
I had the following problem... I grow using the KISS method.
Substrate is pure perlite. PH and EC is fine.
In my veg room all is fine.
But in my flowering rooms I had some leaf issue. Looks like Mg or K def, or both, but in the fact rising the levels of this elements doesn't change anything.
I also have some spyder mites, and fight with theys about 2 month... they still not totally killed.
So most intensive problem I can observe in more bright and sweet spot under HPS lamps.

I suspect offgassing... because I put on the floor the cheap linoleum. and I'm using some PVC pipes to drain and irrigations.

Please help me define the problem, nutes or environment.

So some pisc of problem in different stages:

Thanks

 

[RetroGrow]

Seems like you have to get the spider mites under control, and remove the tiles you suspect of offgassing. I wouldn't wait around with the "offgassing issue", if there is one. Getting rid of the tiles is simple enough. You should see improvement pretty quickly if that was the issue. Then get rid of the spider mites and see if there is improvement. Check your roots also, and I always recommend aspirin to boost plants immune system against insects and disease. One plain aspirin tab per gallon of nutrient solution.
Good luck.

 

[smailer]

Not sure what aspirin can help it's just acid.
In a closest future I plan to change linoleum at the floor to the polyethylene film. but it is too hard job need to relocate somewhere about 500 clones and some equipment.

So any one, can approve or disprove my suspecting?

 

[SeaMaiden]

Aspirin can boost plant immune system, don't be so ready to dismiss. 325mg per two gallons water, can be used as a foliage or root drench. I'm not on my computer, using a new toy, so I don't have the page bookmarked, but Google aspirin water helps plants and you'll find it. Aspirin contains salicylic acid, look that up.

Also, you can't just say the pH and EC are 'fine' and expect people to be able to help you. Tell us what it is! Otherwise, how can we help you to the best of our collective abilities?

 

[smailer]

I had 2 tanks with nutes.

tank #1 filled with RO water + nutes total solution EC 1.5
tank #2 filled with mix RO and tap water + nutes. total solution EC 1.7

Nutes: maxibloom, 1.85g per liter or 7g per gallon.

N 92,5
P 120,99
K 214,97
Ca 92,5
Mg 64,75
S 74
B 0
Fe 1,85

I have 2 systems dripp recirculation and drain tables. Substrate is perlite in both.

pH is 5.8 ±0.2

Temp now 23-25C
Humidity 50%
Lamps 600w

So for the last year I had same symptoms. I had make a many tryings to fix this issue,
change different nute lilnes, water supply, substrates (coco, soil, perlite), increase\decrease air flow and humidity, and etc.

Last what I'm suspecting it's PVC items in my room like pipes, linoleum at the foor. also I had some doubts about foam plastic as my roof insulation.

 

[smailer]

deleted

 

[SeaMaiden]

If you're in the US that PVC should *not* be outgassing, it's to be used for potable water. Linoleum? A little more likely, but linoleum, the real stuff, again should not be outgassing at all. Insulation? That's what I would be suspicious of first.

I agree, your EC is fine, but I think you should have to pH run a little lower, the low-to-mid 5 range. I've run pure perlite and found best results treating it like straight hydro as far as pH goes. That could be part of the problem, but I don't think it would affect the plants to the degree that I see them affected. It is at that point that I agree that you should be considering offgassing.

What changed before you saw the problems in that space?

 

[smailer]

Thanks I do not live in USA, I live near the Russia, and there We have only cheap shit PVC... from China or Poland, Russia, lot of them made in china by license.
I had bought cheapest linoleum from Russia, and totally not sure what factory had any quality control, hush money make business in Russia.

Now I got a polyethylene tarpaulin and become use it at the floor. It's really pain in my ass Now I need to relocate somewhere about 500 clones and tables. I Also plan cover the plastic foam with foil. and hope It will help me save some light and protect of possible evaporation of gas.

In coliseum room I step by step wanna change the linoleum and pipes.
I buy now repoussage pipe. what use polyethylene aganist PVC.

Hope it will help because too much trying and no result for long time...
If some changes has appears I will show it.

 

[joe fresh]

i will say that that is either a ph problem, or toxic salt build up....100% one or the other


flush thoroughly

 

[RetroGrow]

Not sure what aspirin can help it's just acid.
In a closest future I plan to change linoleum at the floor to the polyethylene film. but it is too hard job need to relocate somewhere about 500 clones and some equipment.

So any one, can approve or disprove my suspecting?

Aspirin is not "just acid", it's acetylsalicylic acid.
Why is this important?
Because plants use salycilates in their immune system, and aspirin boosts this dramatically to help fight off disease and insects.
From Wikipedia:

"Salicylic acid (SA) is a phenolic phytohormone and is found in plants with roles in plant growth and development, photosynthesis, transpiration, ion uptake and transport. SA also induces specific changes in leaf anatomy and chloroplast structure. SA is involved in endogenous signaling, mediating in plant defense against pathogens.[3] It plays a role in the resistance to pathogens by inducing the production of pathogenesis-related proteins.[4] It is involved in the systemic acquired resistance (SAR) in which a pathogenic attack on one part of the plant induces resistance in other parts. The signal can also move to nearby plants by salicyclic acid being converted to the volatile ester, methyl salicylate."

Do a little research before dismissing it.
I can assure you it works against most diseases.
Like previous poster suggested, give them (or one pot as an experiment) a good flush.
When in doubt, flush! Can't hurt.

 

[Grønn]

Have you let the pots dry out at any time?

Looks like ph/nute problems from letting the medium dry out too much.

 

[smailer]

I don't have any salts build-up.. I make flush every week with prepared water.
After flushing I have approx 0,5-0,7 EC in drain.

Even just rooted clones moved in flowering room, in a few days start showing same issue.
Certainly young clones I put on shaded place, not directly under 600W hps.
And this clones receive just clear water.

Medium always wet, I use automatic watering.
Roots also looks good and undamaged.

 

[joe fresh]

I don't have any salts build-up.. I make flush every week with prepared water.
After flushing I have approx 0,5-0,7 EC in drain.

Even just rooted clones moved in flowering room, in a few days start showing same issue.
Certainly young clones I put on shaded place, not directly under 600W hps.
And this clones receive just clear water.

Medium always wet, I use automatic watering.
Roots also looks good and undamaged.

i would say thats a big part of your problem right there...flushing a plant causes stress, srastic ph change, and leaches all nutes out of the medium....so if your doing this every week then your never giving your plant a chance...

stop flushing, flushing should only be done when all else fails and ph is off or there is toxic salt build up...

 

[smailer]

English is not my native language and too hard to me explain what I'm exactly mean .

I use prepared water with 5.8pH for flush.
And reload all system after flushing with new nutes, until parameters of drain will be same of the nute solution.

in that way plants no have food about 1 hour only.

Anyway before few cycles I don't make flushing so often but plants had same problems.
As I was write before I have this problem for long time and have to make a lot of tryings and changes in my system and growing methods.

And In this case I have a last assumption what this is offgassing, because pictures in other threads about offgassing so similar to my pictures.

Anyway thanks a lot for help, in weekend I planing change the linoleum in one room and make some observation and photos after it.

I also would be glad hear peoples who personal have offgassing experience.

 

[SeaMaiden]

How about using metal pipe?

 

[Stress_test]

Hello!
I had the following problem... I grow using the KISS method.
Substrate is pure perlite. PH and EC is fine.
In my veg room all is fine.
But in my flowering rooms I had some leaf issue. Looks like Mg or K def, or both, but in the fact rising the levels of this elements doesn't change anything.
I also have some spyder mites, and fight with theys about 2 month... they still not totally killed.
So most intensive problem I can observe in more bright and sweet spot under HPS lamps.

I suspect offgassing... because I put on the floor the cheap linoleum. and I'm using some PVC pipes to drain and irrigations.

Please help me define the problem, nutes or environment.

So some pisc of problem in different stages:
.....
.....................
Thanks

Raise the lamps, increase air flow at top of canopy and move plants away from hot-spot immediately under the lamps.

Oh and get them bugs under control.

 

[smailer]

lamps about 70cm from top of the plants, and now not to hot in the canopy.
Air movement also present.

Bugs just receive

 

[smailer]

So... floor in one room is changed, also I cover plastic foam ceiling with aluminum foil.

Please advice what the distance from lamps to plants tops is ideal?
I use 7 x 600w lamps, without air cooling reflectors.

Plants still not in room and I thinking about hight of tables.

 

[SeaMaiden]

I don't see how covering the insulation with foil will stop these problems if it's really offgassing that is the true source of the problems. You have to allow for stretch when placing lights. Try to set them up so that the height can be adjusted.

 

[smailer]

I had cover celling insulation for minimization of evaporation area and seal the seams.
I'm not sure what plastic foam make some toxic gases, but for more durability I was cover it with 50micron foil.
My suspecting was lied on PVC linoleum in this room, now I had remove it from one room and change to polyethylene tissue.

It was had day, because room was full loaded with clones. And I was almost rebuilt my room from the ground up.