Serious leaf problem, please help

[Oski]

hi

could anyone tell me what might be causing these leafs problems please?

they are at the bottom of the plant but it works its way up.

growstyle is DWC, ph is 5.5-6.0, res temp is a steady 68F, room temp 75F, humidity 50degs, res ec 0.9 fed with canna aqua flores.
before the leaves drop, they become completely necrotic.

this problem is happening in both my veg room and flowering room.

i think its fungal or mg def, but im not sure.

help much appreciated, thanks

 

[sirgrassalot]

Looks like nute burn.

 

[Oski]

ah...... well i never.

i'll lower the ec and see what happens.

thanks

 

[sirgrassalot]

You may want some more opinions on how to correct that if you yourself is not sure. If it was soil I'd say you'd need to flush. I don't know your system. They do look burnt though.

 

[Queso45]

What have you been feeding the plants? That looks like MG def to me. Fill out stitch's questionnaire and help will be on the way.

 

[Oski]

hi

ive taken more pics from plants that this problem is also affecting in the veg room. these are young plants, the roots are perfect.

ive filled in a questionnaire from another site, hope this provides enough info.


HYDROPONICS:

What STRAIN are you growing? mandella kaichakra and other mandella strains
What was the establishing technique? (Were the seed or clone?) rockwool
What is the age of your plants? 5 weeks in veg
What PHASE are the plants in? (seedling, vegetative or flower) are the plants in? veg but also affecting my flowering plants in flower room
What Technique are you using? DWC
What substrate/medium are you using?(Hydroton, RockWool etc.) hydro, DWC
What is the Nutrient temperature? 68F
What Nutrient's are you using? Canna aqua vega and flores
What is the TDS/EC/PPM you are using? 0.9
What is the pH of the "Tank"? 5.8
Are you sure your calibration is correct on your equiptment? absolutely sure
When was your last watering? i top up every day to maintain correct water level
When was your last feeding change? (ie. grow-bloom-micro-additional) once a week
What size bulb are you using? flo's in veg, HPS in flower
What is the distance to the canopy? 2" under flo's, 18-24" under HPS
What is your RH Factor? 50degs
What is the canopy temperature? 75F
What is the Day/Night Temp? (Include flucutaion range) 75F constant in veg, 76 in flower day, 72F in flower night
What is the current Air Flow? (cfm etc.) 160L extract, 2x150A intake
Is the fan blowing directly at plants? no, oscillating over plants
Is your water HARD or SOFT? 0.2ec
Has plant been recently pruned, cloned off of or pinched? yes, light pruning to keep height down
Have any pest chemicals been used? If so, What and When? no
Are plant's infected with pest's - no




please someone help, this problem has been going on for 3 grows now.

 

[sirgrassalot]

Those pictures seem to be showing some signs of Magnesium def, blotchy, twisting & curling from tips than up the sides. Have you looked into the sick guide. I don't know what your pH & stuff should be but look into that. First set of pictures still look like nute burn to me. Just trying to give you some insight.

 

[Oski]

thanks sirgrassalot.

i added 1 teaspoon of epsom salts yesterday to the res - they are in a 30 Liter tubbler and ive heard that in veg, 1/8th teaspoon per gallon of epsom salts is a good addition when using canna aqua, so i figured 1 teaspoon (first dissolved in hot water) should be enough.

im guessing the nute burn in the first group of pics is because they are pics of the plants in the flowering room where ive experimented a bit to see how high i could take the ec. the plants in the last post are young plants which have been maintained on an ec of 0.9 and dont seem to be burning but do have this leaf problem.

should i give them a foliar spray of some epsom salts or maybe another teaspoon of epsom salts in to the res, or just wait to see if the teaspoon ive already added makes a difference?

thanks

 

[sirgrassalot]

thanks sirgrassalot.

i added 1 teaspoon of epsom salts yesterday to the res - they are in a 30 Liter tubbler and ive heard that in veg, 1/8th teaspoon per gallon of epsom salts is a good addition when using canna aqua, so i figured 1 teaspoon (first dissolved in hot water) should be enough.

im guessing the nute burn in the first group of pics is because they are pics of the plants in the flowering room where ive experimented a bit to see how high i could take the ec. the plants in the last post are young plants which have been maintained on an ec of 0.9 and dont seem to be burning but do have this leaf problem.

should i give them a foliar spray of some epsom salts or maybe another teaspoon of epsom salts in to the res, or just wait to see if the teaspoon ive already added makes a difference?

thanks

I'm the dirt type so I wouldn't mislead you. I'm not sure what's the best way to go about fixing it in your system. In dirt yes a spray usually clears up the issue but I think there may be more involved here again in dirt I'd give the first dose a day or two at least before doing it again, the slightest improvement I'd back off. I'm not sure of your quantities etc for you.

 

[MynameStitch]

That is by far no magnesium deficiency, sirgrass has no idea wtf he is talking about.

Convert your EC to ppms, cause depending on which brand you use it can range from 475 to 630......

How tall are these plants?They look like they are getting too much food.
Are you using RO water? Tap?
Are all these strains hooked up to one res?
Which strains are showing the problem all?
What color are the roots?

 

[FreezerBoy]

Don't want to hijack the thread but ...

Convert your EC to ppms, cause depending on which brand you use it can range from 475 to 630......

I thought the consensus was that EC is preferable to PPM because EC is the number all PPM formulas agreed on. Whereas PPM requires multiplying by an arbitrary number no one agrees on.

 

[Oski]

That is by far no magnesium deficiency, sirgrass has no idea wtf he is talking about.

Convert your EC to ppms, cause depending on which brand you use it can range from 475 to 630......

How tall are these plants?They look like they are getting too much food.
Are you using RO water? TAP WATER
Are all these strains hooked up to one res? YES, 30L TUBBLER
Which strains are showing the problem all? ALL OF THEM, SEVERAL STRAINS
What color are the roots?WHITE

....................
....

 

[Oski]

Don't want to hijack the thread but ...

I thought the consensus was that EC is preferable to PPM because EC is the number all PPM formulas agreed on. Whereas PPM requires multiplying by an arbitrary number no one agrees on.

thats what i thought too.

 

[Oski]

bump.

anyone else help please? any more suggestions?

 

[MynameStitch]

NEver heard of that, around here we all use PPM's I am used to going by PPM's
You are the first to say that......


How tall are these plants?They look like they are getting too much food.
Are you using RO water? TAP WATER
Are all these strains hooked up to one res? YES, 30L TUBBLER
Which strains are showing the problem all? ALL OF THEM, SEVERAL STRAINS
What color are the roots?WHITE

How tall are the plants?
You have multiple strains in there which is a problem, because not all strains can be grown the same, some can yes, but having multiple strains and not grown together before not knowing if they can be growing in the same nutrient soloution, lighting and care is asking for trouble. It's a tug of war and someone will win and someone will lose and = lost time and yield.

Looks to me your plants are showing nutrients burn, how often are you testing your PPM/EC and how often are you testing your pH?

Not sure what it is since I am not used to EC, but I do know the plants are not liking it.

 

[DirtDoctor]

EC is preferable to PPM because EC is the number all PPM formulas agreed on. Whereas PPM requires multiplying by an arbitrary number no one agrees on.

Yeah, that's essentially correct. "PPM" is just an estimate based on a reading of the EC in milisiemens multiplied by one of 3 popular numbers. Some people use the 500 scale, some the 700, and yet others use 640.

If you list the "ppms" of your solution without knowing what scale your digital pen is using, then you could be using up to 40% more nutrients than someone using the same "ppms" but a different pen.

The easiest way to understand it is to look at a Truncheon ppm meter - it shows the EC, and all 3 scales simultaneously. Here's a chart tho:


This is why, when refering to your ppms, one should indicate the scale at the same time!

Today I fed my octagon at 1050 ppms(0.7). That's equivalent to an EC of 1.5 - but someone using the 500 (aka the 0.5 Scale) would have called my mix 750 ppms.

 

[DirtDoctor]

so I guess the real question is - what kind of "ppm" meter are You using stitch?

 

[redheadedbitch]

Oski Stitch knows what she's talking about, been helpin peeps for a long time and have only helped their grows. look at the number of posts btw Stitch and sirgrassalots.
I mean this idiot told me to put dog shit on my plants for Calcium def. 1st off, dog shit doesn't have calcium in it and 2nd, the bacteria inside the doggy poo is toxic. my 2 cents lol peaceout~red

 

[FreezerBoy]

I'd follow Stich's advice first as well.

My contention was on EC vs PPM only. As DirtDoctor's chart shows, there are at least three different conversion methods for PPM. There are none for EC. Rather than deal with incomparable products resulting from 3 or more different multipliers, stick with the multiplicand. It's the one thing all ppm formulas require before converting the number to babel.

EC is Popeye. It am what it am and that's all that it am.

 

[inc0gnit0]

listen to Stitch...