16 day old plant, yellowing around leaf edges [with pix]

I have seven seedlings going at the moment, Satori and Kalichakra from Mandala and Tribal Vision from Afropips.

Two of the Satoris are looking unhealthy and have not looked 100 per cent since birth. It's been getting worse lately, particularly the one below. Any suggestions?

EDIT: The points of the affected leaves are pointing downwards

What STRAIN are you growing? Satori from Mandala
What was the establishing technique? (seed or clone?) Seed
What is the age of your plants? 16 days since it broke the soil
How Tall are the plants? 11-12cm
What PHASE (seedling, vegetative or flower) are the plants in? Vegetative
What Technique are you using? (SOG, SCROG etc) Too early to use one
What size pots are you using? (Include how many subjects to pot) 11cm diameter at top
What substrate/medium are you using? What brand of soil mixture are you using?(percentage of perlite, vermiculite...etc?) Shamrock brand seed and potting compost, has about 25 per cent perlite, sphagnum peat moss, trace elements
What Nutrient's are you using?How much of each with how much water? How Often? No nutrients yet
What is the TDS/EC/PPM of your nutrients used? Don't know
What is the pH of the "RUN-OFF"? The ph of the water I use is 6.8, adjusted with pH down
What method of pH test was administered? Using Strips? pH pen? pH pen
How often are you watering? Whenever the pot feels light but the plants are not drooping
When was your last feeding and how often are you feeding?
What size bulb are you using? About 200watts of flourescent lights
What is the distance to the canopy? 10-15 cm
What is your RH Factor? (Relative Humidity) Don't know
What is the canopy temperature? 32c
What is the Day/Night Temp? (Include fluctuation range) 25c-35c
What is the current Air Flow? (cfm etc.) Don't know
Is the fan blowing directly at plants? Yes
Is the grow substrate constantly wet or moist? Mostly moist, though it does dry out a bit before watering
Is your water HARD or SOFT? Not sure. pH is about 8 before being adjusted
What water are you using? Reverse Osmosis (RO)? Tap? Bottled? Well water? Distilled? Mineral Water? Tap water
Has plant been recently pruned, cloned or pinched? No
Have any pest chemicals been used? If so what and when? No
Are plant's infected with pest's? No

Are you sure there's no nutes in that soil? It really looks like a burn. What's 'potting compost'

Noun 1. compost - a mixture of decaying vegetation and manure; used as a fertilizer

I know very little about the soil - there are no ingredients on the sack.

It says it's "specially developed to care for delicate seeds." It claims to have "the right balance of nutrients and trace elements added to high quality Irish sphagnum moss peat... also contains a high level of wetting agents... not suitable for lime-hating plants... can be used when sowing seeds, rooting cuttings and potting plants throughout the year."

I've used this type of soil before for the full duration of grows with no problem. The strains were C99 from GN and Northern Lights from Nirvana.

I'll go down to the gardening centre and pick up one of those soil test kits and report back.

Thanks for the help - I'm always so surprised that people take the time out to try to diagnose the problems of plants belonging to people they don't even know. Very generous.

I think your problem might be in your tap water. There could be a lot of magnesium in it which could be screwing up your plant. When you say your PH of your water is 8 until you adjust it... what are you adjusting with? What is the PH after you adjust?

A PH check of your runoff from your soil should reveal some information. However, I have heard that those soil PH kits aren't very accurate. If you are looking for a second opinion on your PH... why not give pool test strips a shot. They are used for checking levels in your swimming pool, but are very accurate for measuring runoff water from your plant. They come in packs of like 100 strips for 5 bucks.

If I had to take a shot in the dark, I would tell you to switch your water to RO.

it seems to me the r/o water would be the best i had this problem and that what i did and i have been using every since then with heathly plants
you will lose all that is sick thou

I reduce the tap water with GHE dry pH Down and get it to about 6.8, sometimes a little lower.

I am pretty confident the soil I am using is alright, so tap water is probably the thing to focus on. While I try to sort out RO water, is still bottled mineral water any better than tap water?

Thanks for the help

EDIT - background information: I had some sick Black Dominas recently. They were about four weeks in veg and looking pretty rough. I stopped the nutrients and just watered then for 2 weeks with unadulterated tap water - no pH adjustment - and they recovered really well. Don't know if that sheds any more light or makes things more confusing....

Around this age you don't want to use RO water on the plants, it has no micros and unless you have a compelte fert with micros, RO water should be avoided on seedlings due to no micro content, even though they get food from soil and you, they need supplements during the period before there next feeding and when you use water to feed them they need the micros.

If you have hard water, get a filtration system put in, like a water cleaner type.

Do you let your water sit out before using it?

not suitable for lime-hating plants...

Click to expand...

If there is that much lime in the mixture and you are using tap water your plants are getting too much calcium and magnesium, hence why I said "water too hard" mix those 2 together and the problem will mimic a hard water problem.

Also, the pH down you are using:

• Nitrates in a form slowly assimilated by the plant and harmless to the flowering process.
• Phosphates for flowering, but for healthy roots, lush foliage and harmonious growth too.
• Plus some magnesium, sulphur and microelements.

ALSO has magneisum and possible calcium, so the plant is getting way too much micronutrients...... again like I said the plant is mimicking hard water problems, but you have a toxcicity problem of micros going.

When your water is hard your plants can't absorb nutrients as well, because the abundance of too much magnesium and calcium.

WHat I would do is flush those plants A LOT with a few gallons of water.....

Peat moss is acidic so they added lime to adjust the pH to try to make it neutral, but cannabis likes a acidic soil when it's soiless and your mixture is considered to be soiless.

That is NOT nutrient burn like sirgrass has suggested it was.

Can you get a few more pictures of the plant from the side? so I can see the lower leaf the color it is?

Have you tested the run off water that comes out of the pot?
You should not be using pH adjusters until you know the final pH value that comes out of the pot.

They were about four weeks in veg and looking pretty rough. I stopped the nutrients and just watered then for 2 weeks with unadulterated tap water - no pH adjustment - and they recovered really well. Don't know if that sheds any more light or makes things more confusing....

Click to expand...

Yes it does, it just further proves what the problem is.... were they too in the same mixture as these?
considering your pH adjusters have micros and you feeding them would be too much, plain tap water flushes anything out so with you giving them plain waterings and no feedings you slowly leeched excess out of the soil which is why they recovered.

The problem is there is too much micros coming from the soil and the pH adjuster you are using, I would flush the mixture out really good and stop using that brand of mixture.

Also would get a pH adjuster without micronutrients.

You haven't convinced me of that & of course a flush is what's needed if they've been nute burned. I'm also not here to point out others responses but to offer my assistance. Try it.

You offer assistance, but your "assistance" is conflicting sometimes. When you help out is fine, more people the better, but you don't "look into details" you miss a lot of small details that is very important in why the problem is occuring. If you think that the amount of calcium and magnesium the plant is getting is normal, you need to go back and re learn how to grow. Especially given the size of the plant.

I am not here to outpost others and I don't need to convince you, that is not what I am here for, I am here to help out others and make sure they get there problems fixed and for them to get proper information on there problems.

Is this the ask stitch board or is it a public forum. We have different methods mine works great with less complications. Just like your rant on the guide that didn't change. Mine is better simple as that.

Simple is not alway the answer to things espeically when trying to come on here and help out a grower with his plant that is not even yours;' you NEED EVERY DETAIL and this is a public forum and your rant on Is this a stitch board makes no sense and you are the one who said "You haven't convinced me of that" and I told you why I said what I did and now you come up with some smart ass remark. You got something to say to me, say it to me in a PM, but do NOT go around trashing someones thread.

No sneaky pms here dear. I don't do that thanks.

I said what I thought about your info like you chose to critique mine. If you want every detail ask the poster.

I already gave my reason why I critique yours and I am not playing a troll game with you, so whatever you post next I am not answering, I am not going to keep repeating myself why I said your post was wrong, if you can't read clearly I suggest you get glasses. You don't want me to critique your posts, then make sure the information you post will be correct or not misinformed.
Sneaky PM's? Fine, then like I said, don't piss away someones thread then since you don't want to take it up in a PM.

Ohh you wanted to talk something over with me go ahead you know my pm. I meant I wouldn't use it like you did with me, to interrogate a new poster under the guise of being friendly. Send away. I see how you get that post count up.

Pictures as requested

Thanks for the help everyone.

So what I am planning to do is:

1. Check the pH of some unadulterated tap water, water the plant, then check the run off to see what the pH is then. I'll report back here

2. Flush the plants out with plenty of unadulterated tap water. [Does it matter that the pH of this water will be around 8?]

3. Transplant. Are they ready then for a mild dose of nutrients? I have Dr Hornby's Iguana Juice Grow

Question:

>> The problem is there is too much micros coming from the soil and the pH adjuster you are using, I would flush the mixture out really good and stop using that brand of mixture.

Do you mean change the brand of soil I am using? I have some bio-bizz allmix lying around

Yup, I would flush man, rinse all the lime and pH left over in the soil from your pH adjuster. First I would water your plant and collect the run off and test it to see what the run off pH is. Either way you have way too much calcium and magnesium in there and it has to be removed. Hard water damage makes nearly the same markings and coloring, so I would flush with around 1 1/2 gallons of water, prefably RO water if you can, if not tap water will do ok, but you would get a better flush with RO considering your problem is with micronutrient toxicity.

Edit: I posted right after you and did not realize you posted again!

2. Flush the plants out with plenty of unadulterated tap water. [Does it matter that the pH of this water will be around 8?]

No, it does not matter when you do a flush.

ps are there any pH adjusters you'd recommend that do not use micronutrients?

GH pH down ( General Hydroponics)

Also your problem was a combination of things, the soil is what caused a lot of it, but combined with your tap water already having Calcium and magnesium and your pH adjusters did and the soil already had a lot of it in there it combined together causing all this.

I would not use the soil mixture anymore, seed starter mixtures are fine to use and safer, but the mixture you picked out is not good for cannabis.
They added way too much lime to counteract the acidic ness of peat.

All mix I would not transplant them in right now, they are damaged right now, I would wait 2 more weeks before putting them into that mixture.

Right now worry about flushing them with a lot of water, the more water the better to help flush out the lime in the soil and left over pH adjusters.

If you flush it out right the pH should go down and you would not need to use as much pH adjusters or maybe none at all.

2 be on the safe side i would use 2 gallons of water for a flush, since lime is long acting it will take a lot of water to flush it out. After that you need to water your plant with plain water next time it needs water. I would get a different mixture, seed starter mixture and mix it with all mix for now. Get a different seed starter mixture to water it down, but ensure it is not full of lime if it's got peat moss in it. Since all mix is soiless, I would find a seed starter mixture that has peat moss in it, but not a lot of lime added, some lime is needed depending on how acidic the peat is, it varies with different types.

But avoid using when it says not for lime hating plants

Thanks for all that. Are you suggesting I use GH pH Down? That is what I am already using.

Anyway before I go any further the results of the run off test:

- The unadulterated tap water I had before watering the plant was 7.7
- The run off using that same water was 5.9-6.0.

What does that mean?