Northen lights Problem ( humidity )

Hey guys. some info of my setup.
MH 250 w , w cooltube
2x2x5,5 - 60x60x160cm,
displacement around 4 Inches from plants ( 78 fahreinheit at highest )
Humidity goes from 40-55 %
soil is light mix, bio bizz. bio-grow as nutrient. ( same soil before and after transplant )
9L = 2US gal. Watering when dry reaches some inches down.
Latest feed was 6 th of feb, 2,6 ML of nutrients per litre, Plant was at this stage 24 days above soil. I only water around 2 Litres per pot, get some draining.

I currently have 2 northern lights in my grow cab. as of the 6th february i Flushed one of them and gave the other nutes ( 2,6 ml /L ). 2 days after the NL wich recieved nutes got greener so i thought i locked in the problem to nutrients-deficiency. the other one showed no signs of anything but slow growth.First time they got nutes was at half strengt, at day 17.
.
The problem started with small dots that got brown, no yellowing anywhere. it died of and shows a brown colour, crispy at touchat the end of leaves, first leaves set i might add.
I had wicked sick growth the first 2 weeks, when light was on humidity were about 50%, and since i connected fans etc to timers and took me nearly 2 weeks to change this so there would be airflow even when the light was off. In this time when light was off humidity were always 91 %. Problems came when i changed to a stable humidity 40-50 %. could my plants have gotten so adapted to this high humidity? I have 2 jack herer in there and these babies still grows like damn, they have very little of the sick-signs that NL have, maybe they adapted faster? ( they still got the same signs thou but small)

So from the 6 th feb to 10 feb the problem got pretty much neutrilized with added nutrients (2 days after when i saw change between the flushed one and the feed one i gave the flushed the same amount of nutes since i thought i locked it do deficiency, more exactly i thought it was cal/mag.
But now when i got home the 11th the problem got bigger, the "crispyness" have taken over more leaf-mass ( ??!). My jack herer drink its water in about 2-3,5 days, the NL want around a week to finish it ( got perlite in the soil)
I couldnt say the NL grow slow but comparing to the first 2 weeks it´s like superman vs snail. to mention also that the 2 first week i had 25,5 celcius int he day and low 16 in night, developing very nice purple colour, got a little afraid the difference was to big so i finally eased up on my self and put on the heater first time since in moved into this flat, now they get 20 celcius at night.

I´ve been wondering in the last week to post this so here it is. ( the cops will come and bust my chops haha )
In the first picture there is NL 1 that gt flushed wich now is worse, right behind of NL1 we got the second, the problem got bigger on this too but not as much as you can see on picture.

picture 2 is just a bonus picture, you cant see much but its in 29 days of veg, Jack herer it is, LST almost every day. dont allow it to breech my rules for one second. Not topped and we got 16 side brancing coming out nice, getting big and fat with 7 big side brancing and the other ones getting bend to their right place.the stem is thickness of 1 and ½ cigarette ( oh on this there is one or 2 leafs sshowing the same sick signs like NL.)


Id like to sort this problem myself but ooh darn its gettin worse, my first grow and am already smoked all the hash and told myself not to smoke more until harvest. yeah right

On behalf on non english spoken countries i´d like to hope my english isnt all that waste. so bare with this text

if theres some interest i´d could breach my code and start up an late grow-journal

// SeddaN

edit: I might add i water with Ph going in 6,8 and 6,3 out. 271 in hardness, i leave water in bottle for 24 hrs open hoping for something.

If your question is about humidity those numbers are right on. They may have stressed a little going from 90% to 50% but, they should snap out of it. I'd also raise my lamp 8-12in from the tops. Good Luck!

i think you stress them fro humidity and the cold when lights were off give them time should recover

thanks. Ill update tomorrow or the 14 th so yall know whats up. humidity is my best guess and lets hope the leaves stay like this or just die off, no spreading thanks

So we meet again Rui. Thanks for helping out.

13 of feb, 31 days above soil. 7 days since last watering. will be feed/watered tomorrow depending what answers i might get
Every plant still shows the problem, in percentages its 25,20,10,3 % where 25% would be the coverage od the leaves of the entire plant.

Heres first a picture of the "real problem plant", I tried to shot somewhat the same like in the first picture in this thread. northern lights x1

Problem spreading inwards. some small signs on other leaves



This 3 pics are from jack herer x1, biggest plant in the cab. picture shows development from the first real set of leaves, lets call it node 1 -2 - 3

1 , Many spots, browning


2, Some "pre spots" on second


3, Looks okay, heavy greenish colour, not to heavy but on the brink to what overfeed looks as to google pics. new growth etc is in less green colour.



Fifth picture shows some average signs of how it looked when it started.


The growth is on average okay, got nothing to compare too. takes approximately 7 days for plant to dry out soil. been feed twice , BIO-GROW , first feed along with transplant 14 days, rootbound , 1,3 ML / litre. second feed 2,66 ML / litre.age 24 days.
Thinking of addind bio-bloom along with next feed, not in flowering yet thou.
these pots are US 2 gals pots, 9 european litre

10 days to dry out first time, 7 days to dry out as of today.

Am off for some kebab, bounce back in a sec!

If your not in flower why use bloom nutes? I'd concentrate on keeping them nice and green using N. There's plenty of time left to begin using bloom nutes. Also, bloom nutes will help turn your leaves yellow. 7 days seems like a long time for them to dry out. Did you add any perlite to your medium?

It was just a thought i got haven´t poppep the bottle. anyway its bio bizz light mix and contains perlite. from what i understand its almost a soil-less.

Jh 1 wich doesnt show much of this problem is watered more frequently, 2-4 days depending on me.

edit . could it be a multiple defieciency?like i said am only using the grow. maybe add some mag cal, think alg-a-mic contains just those plus more. the soil contains hardly anything. water carry mag/iron/zink and so on but maybe my water doesnt contain much?