Michigan Thunderfuck Leaf Browning/Crisping up - Month into flowering! please help

[clp]

Alright guys,
we have a little problem here. We got gifted these seeds and are not sure what they are to be honest. We have heard that Alaskan Thunderfuck is one of the best strains of all time (although neither of us have smoked it) n it sounds kickass so we decided to go with the nickname of - Michigan Thunderfuck for these gals . The bigger, more mature fan leaves are browning. First it was just in the grooves of the leaves but now it has spread to the entirty on a couple leaves. It started about a week n a half ago but has gotten much worse in the last couple days. It only effects about 5 or 6 leaves though.
This plant has undergone tons of stress but is now looking very healthy and is budding well besides the browning of the couple leaves.

We induced flowering on these plants a while back as a test not thinking they would make it (they were stressed badly) but suprisingly BOTh turned into females and are budding nicely now. To keep them in 12/12 while we vegged other plants in the dr150 tent and put them into bedroom outside the tent. They had a little bit of light leaks coming in but nothing too major. We really werent planning on keeping them so we had to do it sloppy :/

Here is the questionare thing all filled out

How long has this problem been going on? - Week and a half or so - Got semi-bad recently
What STRAIN are you growing? - Random Dro seed provided by fellow grower
What was the establishing technique? (seed or clone?) Seed
What is the age of your plants? 2 months in veg then month into flowering.
How long have they been in the soil mixture they are in now? - 2 weeks
Were they in the same mixture when they were seedlings/smaller plant? If not, what mixture were they in before? No - They were in Miracle Grow Moisture control - Bad idea I know :/
How Tall are the plants? - 2 feet
What PHASE (seedling, vegetative or flower) are the plants in? - Flowering
What Technique are you using? (SOG, SCROG etc) - None - Straight up
What size pots are you using? (Include how many subjects to pot) - 3 gal grow bag
What substrate/medium are you using? What brand of soil mixture are you using?(percentage of perlite, vermiculite...etc?) - Was in 2 ltr of Miracle grow moisture control - Now is in FFOF, FFLW, FF Big n Chunky perlite - 50/25/25
What brand Nutrient's are you using? FF Tiger bloom and FF Big Bloom
How much of each nutrient are you using with how much water? *Knowing the brand is very helpful* - 2 tsp per gal -
How often are you feeding? Once a week
If flowering, when did you switch over to using Bloom nutrients? - One week in
What order are you mixing your nutrients? (example: veg nutes 1st, bloom 2nd ect) - Both bloom nutrients
What is the TDS/EC/PPM of your nutrients used? - not sure no meter
What is the pH of the "RUN-OFF"? - Will check after next water!
How often are you testing pH/ppm/EC/TDS? - Need to more, once every week maybe?
What method of pH test was administered? Using Strips? pH pen? - PH meter - electronic
How often are you watering? - Every 3 days or so - We use lift test and a moisture meter
When was your last feeding and how often are you feeding? - Saturday was last feeding - weekly
What size bulb are you using? - 1000W MH
How old is your bulbs? - Almost new
What is the distance to the canopy? - 17inches
What is your RH Factor? (Relative Humidity) - 45%
What is the canopy temperature? - low to mid 80's
What is the Day/Night Temp? (Include fluctuation range)- Was on 20/4 or 24/0 so not sure.
What is the current Air Flow? (cfm etc.) We have a 250 (I believe) can fan attached to C.F. cooling the dr 150 tent
Tell us about your ventilation, intake exhaust and when its running and not running ? - We are aircooling the lights with a 750 CFM fan. The 5X5X7 room is being cooled by a 250CFM can fan/filter combo and is ducted to exghaust into the attic.
Is the fan blowing directly at plants? - no
Is the grow substrate constantly wet or moist? - no, we let it dry out somewhat.
Is your water HARD or SOFT? - RO water
What water are you using? Reverse Osmosis (RO)? Tap? - RO Bottled? Well water? Distilled? Mineral Water? - RO
If using tap water, what is the ppm/EC/TDS of the water right out of the tap?(Only if you have a tds pen)
If using RO,Distilled,mineral water, what is the ppm/EC/TDS without any additives?(Only if you have a tds pen)
Are you using water from a water softener?
Has plant been recently pruned, cloned or pinched? - It's been pruned slightly - nothing major
Have any pest chemicals been used? If so what and when? No
Are plant's infected with pest's? No, dont think so

Here are some pics



Please help with this problem IC. We don't want it to get worse :/
I believe the problem is due to over fertilization or nutrient lockout for some reason but need some real diagnosis.
Thanks!
CLP

 

[clp]

Looking in my grow bible it seems that a possible Phosphorus deficency may be going on? Maybe I'm wrong though.. The pics seem to look quite similar but I feel that we are feeding it enough fertilizer to provide phosphorus. She is still in pretty fresh soil also.

 

[clp]

Any advice guys? These gals are getting progressively worse.. :/

 

[darrmann]

id say looks like heat stress. at 80 not overly hot but at 17" pretty close for a 1000

 

[twiztidbudsmoke]

I agree about the light raise it to 2 ft and throw an oscolating fan to blow on your girls and cool them down. If you think you burned/overfertilized recently you should go with strait water and see if the problem clears, if it doesnt they are deficient.

 

[clp]

I really don't think this is heat stress.. They were closer than this and have been at this light level for a while. It's also primarily leaves lower on the plant, the top bud/cola looks perfectly fine.

We are only watering w/ straight RO water for a while on these guys until we figure out what the problem is!
Any more help IC

 

[Stinktoe]

how orig.

 

[paint4420]

my kush bag seed is doing the exact same thing around the exact same time

curious to find out if it is a P defficiency

i treated my girls swith some molasses and more ferts to see if that would help her at all

 

[clp]

The Michigan Thunderfuck is a made up name We just wanted something to call her since we were tired of calling her bagseed or random dro seed hah.
We got it gifted from a grower friend..

Any other advice? The problem is progressing to some of the other leaves.


PLEASE HELP IC!
This plant is getting worse!

 

[clp]

We are now thinking it is a magnesium deficiency possibly? Any confirmation on this?
We are not using calmag or epsom salts..

We will be adding blackstrap mollasses into the mix if it will help things.

 

[darrmann]

heat stress can show up on any part of plant. The longer in flower the more you need to move up. I have 8 1000's and a fan blowing temps at 75 degrees with lights and I have my lights at 24". In fact I got heat stress last run with them closer. Know let me say I started them at 15" then as they get older the more they are apt to get heat stress. Also give them some superthrive and silicate for stress and better water absortion. ok goto this site im going to give you and goto heat stress towards the bottom and read it. alos has every deficiency and other problems. Its a great reference i would bookmark it . I did.

http://www.icmag.com/ic/showthread.php?t=11688

 

[darrmann]

my kush bag seed is doing the exact same thing around the exact same time

curious to find out if it is a P defficiency

i treated my girls swith some molasses and more ferts to see if that would help her at all

it is definitly NOT a potassium deficiency

 

[darrmann]

We are now thinking it is a magnesium deficiency possibly? Any confirmation on this?
We are not using calmag or epsom salts..

We will be adding blackstrap mollasses into the mix if it will help things.

magnessium deficiency shows in a totally different way. it lightens up all the outer parts of the leaf leaving the inner part dark green. I dont think its magnessium dude.

Darrmann originally from mi. know in cali.

 

[darrmann]

This picture is what light bleaching/ light burn looks like.
Only way to fix this is to Move the lights away from the plant!
Or make sure you dont go over 75 watts a sq foot, or your plant will have to much light and light bleaching can occur anywhere on the plant. (indica species seem to bleach easier than sativas imo.)

 

[darrmann]

just reread your original post and you really need to get that rh up to around 60 at the lowest. I would also use cal mag every other watering or at least once a week. Also superthrive for stress and a root conditioner like hygrozyme, keeps your roots healthy and free of disease.and lastly a silicate3 like pro silicate to reinforce plant walls cells and helps with heat and cold stresses.all these are pretty important to have. also if your having a problem with nice heavy tight buds use a booster in the 5th week of flower.

 

[paint4420]

lolz darrmann probally a brain fart but just lettin ya know

P= Phosphorus the chemical element that has the symbol P and atomic number 15

K= Potassium is the chemical element with the symbol K atomic number 19

im still on the fence with this one on the actual cause. but after applying up some bloom fertz and adding in the black strap they arnt looking any worse, my assumption is the damage will not get any better im just trying to stop it the last few weeks my ladies are alive and kinda well

im still suprised i havnt killed my girls yet they suffer all sorts of crazy things like light and heat stress constant mollesting for good smells! nute burns nute defficiencys but damn do those flowers look oh so tastey!

truley a miracle of nature that so many people can actually grow these things

oh one thing i wanted to add that i have thought of and darmann mentioned that couldnt hurt was hydrozyme if your not familar it is an enzyme that breaks down the dead or decaying root matter into digestible material by the bacteria on the roots. basically increasing root health! lol but i would like to do more reasearch on enzymes before i pay 40 bucks for a bottle of it

the molasses seemed to help the plants relly well with absorbing water, i noticed the oldest and most mature of my bag seed was having difficults drinking her soil dry but after the molasses she sucked it all right up! i was very suprised at the result! and im wondering if it has to do with the carbohydrates feeding the bacteria and helping the enzymes already in the soil

just my lil theory

 

[darrmann]

lolz darrmann probally a brain fart but just lettin ya know

P= Phosphorus the chemical element that has the symbol P and atomic number 15

K= Potassium is the chemical element with the symbol K atomic number 19

im still on the fence with this one on the actual cause. but after applying up some bloom fertz and adding in the black strap they arnt looking any worse, my assumption is the damage will not get any better im just trying to stop it the last few weeks my ladies are alive and kinda well

im still suprised i havnt killed my girls yet they suffer all sorts of crazy things like light and heat stress constant mollesting for good smells! nute burns nute defficiencys but damn do those flowers look oh so tastey!

truley a miracle of nature that so many people can actually grow these things

oh one thing i wanted to add that i have thought of and darmann mentioned that couldnt hurt was hydrozyme if your not familar it is an enzyme that breaks down the dead or decaying root matter into digestible material by the bacteria on the roots. basically increasing root health! lol but i would like to do more reasearch on enzymes before i pay 40 bucks for a bottle of it

the molasses seemed to help the plants relly well with absorbing water, i noticed the oldest and most mature of my bag seed was having difficults drinking her soil dry but after the molasses she sucked it all right up! i was very suprised at the result! and im wondering if it has to do with the carbohydrates feeding the bacteria and helping the enzymes already in the soil

just my lil theory

yea I realized I screwed up shortly after I posted that. Thx for straightning that up. dont want to screw up a noob looking at it lol.

 

[paint4420]

clp, how are your girls comming along? i have yet to see anymore symptoms arise after trating with bloom fertz with a high P rating. stilll not sure if it was the cal mag or the P but it has stopped fer sure!

 

[Hydrolized]

You are in RO, I would try some Cal-Mag, check for root aphids too!

 

[KMothsi]

I disagree with the Heat claims being made. Been growing for several years, had this happen once during my first grow after switching to RO. If you are going to use RO, you must supplement with a Cal/Mag Nute. No doubt about it. If you're not, I'm actually surprised you made it this far without more problems. Get something like Botanicare Cal/Mag and supplement at 5ml/GAL.

Just as a word to the wise, however, some plants require different levels of Calcium and Magnesium, so getting a bottle of pure Mag (Organicare Magnesium) is also a good idea-- it's real cheap. Cal and Mag are the first salts absorbed by the plant, as they activate the 'pumps' that bring other salts up through the roots. So, when you have Cal/mag problems, it can be really confusing, as it can very easily manifest itself as a number of strange leaf and growth problems. Similarly, be careful adding too much of either element, as this will mess with the salt uptake.