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UK420 > Cultivation > Problem Solver > Sick Plants
SirBob
Hello all, i have 12 Pot of Gold clons in my new Home made NFT system.
Some have started to show a bright yellow colour on the leaves. sad.gif

They have been in there roughly 5 days now, and roots are emerging from the bottoms of the 3" cubes
They are in Canna Aqua Vega. I did have them at 1.27ec, but i have noticed the ec rising, so i have reset it to 1.02ec. Ph stays very stable due to the large (130l) res tank.

They are under 400w MH
Temps are around 26oC-30oC with very good air circulation from two Ruck 125mm L Fans (int. & ext.)

All plants continue to grow, but some are doing better than others.

Here are some shots of the worst affected plant, and the healthiest plant. I think i can see some of the deficiency on on of the fan leaves of the healthy one, but it is very faint.

funky worm
Magnesium deficiency.
SirBob
Here is a couple of shots of the healthy one, and a comparison:

From the ec rising i would think it could be nute burn, but i thought that affected the tips of the plant? unsure.gif
I would be very greatful if anyone has any ideas, if you need any more info please ask.

Bob yinyang.gif
SirBob
Comparison
tom o'rite
Your info is pretty complete but perhaps you could let us know if they're spinning at 33 or 45 rpm, please?
funky worm
lol.gif! maybe bob is scratching too much and they get lightheaded from all that...

SirBob go git some epsom salts, and mix it in the nutrient solution at a rate of one flat teaspoon per liter for a day or two to cure that magnesium def.
se7en
QUOTE(tom o'rite @ Aug 23 2006, 10:27 AM) [snapback]662123[/snapback]

Your info is pretty complete but perhaps you could let us know if they're spinning at 33 or 45 rpm, please?

rofl.gif rofl.gif rofl.gif rofl.gif rofl.gif rofl.gif wink1.gif
mg deficience i rec they are to young for that.... yinyang.gif
funky worm
What does plant age have to do with Mg levels? Please explain lisbon23
SnAp CrAcKLe pOp
Hello sir bob,

yes i think your right alittle hard on the nute back it off just a touch even the healthy one is showing earliest signs if you keep going at this strength there will be more burning.

Could also have got alittle close to globe but im thinking nute before fire. wink.gif


Nute level?

2 weeks ago and now.


Mag def

Have you been feeding regularly and is the nute your using of hydro type suited to rock wool, two ways of getting deficiencies im aware of.



Your plants are way too healthy to have deficiencies of any major level, deficiencies dont happen overnight like burning can.

if plant was stunted spotted or rusty and Fugly maby but burn in just some higher leaves hmmm dont know.

Goes searching for your diary SCP
SirBob
Hello all, many thanks for the replies. smile.gif

lol.gif they are indeed spinning at 45, this allows for optimal light pread and coverage.

mad.gif Mag def? Fukkin Mag Def??? That's half the fucking reason i quit compost, i thought hydro didn't suffer from bastard magnesium deficiency??? doh.gif Ive also got a fucking 140litre res, and only a little epsoms left. grrrr........ It does look spot on like mg tho, ill chuch the rest of me epsoms in there tonight, and get a fresh supply 2morow.

SCP im using canna aqua, which is designed for recirculating systems, i.e. NFT

I cant really see it being too close to the light, it is 12 inches away and there is a huge gale blowing in there from the fans

This didn't come on overnight, it has been a slow change since i put them into the NFT system, about 5 days ago.

Ill check the nutes tonight to see if there have been any fluctuations.

Thanks All!

Bob yinyang.gif
funky worm
No frets mong! Use a half teaspoon per liter epsom salt foliar - it will rectify the situation fast! note that the yellow wont go green again...

Check the pH, if its too high you bound to get this kinda prob, did you remember to treat the rockwool...

Magnesium deficiency is often caused by water thats full of carbonates.. in english its called soft water I think, its what causes buildup of scale, calcium carbonates etc
SirBob
QUOTE(funky worm @ Aug 23 2006, 03:43 PM) [snapback]662402[/snapback]

No frets mong! Use a half teaspoon per liter epsom salt foliar - it will rectify the situation fast! note that the yellow wont go green again...

Check the pH, if its too high you bound to get this kinda prob, did you remember to treat the rockwool...

Magnesium deficiency is often caused by water thats full of carbonates.. in english its called soft water I think, its what causes buildup of scale, calcium carbonates etc


hi mate, unfortunatly i dumped all the epsoms in the res (mixed in a small amount of water first btw)

ph is fine, about 5.9 atm.

when i transplanted the clones i soaked the 3" cubes in 1.10th strength nutrients at ph5.8 for 24 hours, would this be ok?

I think you mean hard water which has all the shite in it, and yes my water is especially hard. sad.gif I think im gonna get a RO filter to fight back, ive had no end of mg problems. Thanks Mate!

Bob
pixovilson
so, am i right in thinking that iv got a mg def, iv got yellowing leaves too, but the 1st leaves (the round 1s) are all yellow and the 2 2nd leaves are turning yellow(ish), i take it thats mg def, iv got epson salts, so 1 tablespoon to a litre ov water should fix it up then...... guitar.gif
d|t
Nutrient Deficiencies

freakje
i soak mine with ph level between5.3 and 5.5 (rockwool is innert medium and the ph level of it is between 7.0 and 8.0. so if you start low and soak them,after 24 hours pick up one cube and let the drain go at the end of the drain put a bukket under the cube and take that water,
ill bet that if you are beginning with ph 5.8 youre ph level @ 24 hours is between6.3 and 6.6
thats a little bit to high for the begin.
freakje
wow as i was reading and telling i totaly forgot to explane my story of youre problems lol.gif..
i am thinking magnesium ,but it could be also a zinc problem.
i give an explanation :

Magnesium helps supports healthy veins while keeping a healthy leaf production and its structure. Magnesium is significant for chlorophyll-production and enzyme break downs. Magnesium which must be present in relatively large quantities for the plant to survive, but yet not to much to where it will cause the plant to show a toxicity.


Magnesium is one of the easiest deficiencies to tell… the green veins along with the yellowness of the entire surrounding leave is a dead giveaway, but sometimes that’s not always the case here. In case you have one of those where it doesn’t show the green veins, sometimes leaf tips and edges may discolor and curl upward. The growing tips can turn lime green when the deficiency progresses to the top of the plant. The edges will feel like dry and crispy and usually affects the lower leaves in younger plants, then will affect the middle to upper half when it gets older, but It can also happen on older leaves as well. The deficiency will start at the tip then will take over the entire outer left and right sides of the leaves. The inner part will be yellow and or brownish in color, followed by leaves falling without withering. The tips can also twist and turn as well as curving upwards as if you curl your tongues.


Excessive levels of magnesium in your plants will exhibit a buildup of toxic salts that will kill the leaves and lock out other nutrients like Calcium (Ca). Mg can get locked out by having too much Calcium, Chlorine or ammonium in your soil/water.
One of the worst problems a person can have is a magnesium def caused by a ph lockout. By giving it more magnesium to cure the problem when you are thinking you are doing good, but actually you are doing more harm then good. When the plants can’t take in a nutrient because of the ph being off for that element, the plant will not absorb it but it will be in the soil… therefore causing a buildup. A buildup will be noticed by the outer parts of the plant becoming whitish and or a yellowish color. The tips and part way in on the inner leaves will die and feel like glass. Parts affected by Magnesium deficiency are: space between the veins (Interveinal) of older leaves; may begin around interior perimeter of leaf.


Zinc plays a lot of roles in the plants, first off zinc aids in the plants size and maturity as well as production of leaves, stalks, stems and branches. Zinc is an essential component in many enzymes as well as growth hormone auxin .Low auxin levels can be the cause of stunting of the plants leaves and the shoots. Zinc is also important in the formation and activity of chlorophyll. Plants that have a good level of Zinc, can handle long droughts. So that’s why Zinc plants an important role how it absorbs moisture.


Zinc deficiencies on some plants will have the Spotting and bleached spots (chlorosis) between the veins first appears on the older leaves first, and then goes on to the immature leaves. It will then start to slowly affect tips of growing points of the plants. When the zinc deficiency happens so suddenly, the spotting can appear to be the same symptoms to that of an iron and manganese, without the seeing the little leaf symptom.
Zinc is not mobile in plants so the symptoms will occur mainly in the newer growths. Having a plant that is deficiency in Zinc can cause small crops, short shoots and have a cluster of small distorted leaves near the tips. Between the veins (Interveinal) yellowing is often combined with overall paleness. Pale or grayish, yellowing between the veins; rosetted weak is the signs of a Zinc deficiency.
With a low level of zinc in your plants, your yields will be dramatically reduced.
Interveinal chlorosis is present in the small, narrow distorted leaves at the ends of really shortened shoots and the shortening between internodes. Leaf margins are often distorted or wrinkled. These nutrients will get locked out due to high pH: Zinc, Iron, and Manganese. These deficiencies will often occur together. Parts affected by a zinc deficiency are young leaves and petioles.

Having an excess of Zinc is very rare, but when it does happen it can cause wilting and in worse cases death.
i stay on magnesium but keep the zinc story in youre mind..
good luck freakje
eek
hi Ah

jacking this for a post> ph34r.gif

Great last post. I have similar problems, pretty much identical. Ruling out Mg as i fed their second Mg dose a few days ago. solved the creeping deffs in the lower regions. roughly 3weeks into 12/12 and 3ft high.

a little Zinc is my next port. I had swapped over my bulbs fearing old bulbs bleach tips. cheers freekje for the detailed Zinc info. Taaaa SirBob for starting it up (1st post ive seen with identical problems)

uuum Whats got Zinc in smile.gif?
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