Need help identifying the problem

Greetings,
this is my first grow and about a month in. My plants have started to be struggling and I am not sure why. New leaves grow more pale and yellowish and old ones suffer too. I have a 4x4x6.5 grow tent, a fan as seen in the picture bellow and an inline one to extract (305 m3/h), passive air intake left corner. temperature during the 18 light hours stays around 23C/73.5F and humidity at 60-65%. During dark hours temperature falls at around 18C/64.5F and humidity rises at 70% and even reaches 85%. Could this be a problem? I have started opening up the tent grow at night to keep it lower. I am watering once about every 2 days checking how wet is the soil. I haven’t used any nutrients until now, first day is today. I have them in an image bellow, mixed 2ml with 1 liter water and shared it to the four plants.
For lighting I am using a 400W hps dimmed down to 250W. Bulb specificetions bellow.
Light+fans setup:


Bulb:

Bulb:

Nutrients:

My plants:

Struggling lef:

Turning yellowish:

Most struggling plant:

Soil:

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Take a deep breath, relax, things will be all right. Check the levels and the illustrations above to get started, and wait for everyone else to wake up and reply.

Call in the artillery - @TheMadFlascher @sssportsmfg @nacho151 @sdoyle @PreyBird1 @Dog_Fart1

Shooting from the hip it looks as if you are in need of nutrients, specifically I would try a little CalMag and Nitrogen. Again wait for everyone else to wake up and chime in.

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Well I suspect nitrogen deficiency. Looking at what I assume is the label on your soil mix it could also have a pH issue. The soil maybe adjusting the pH to 7 to 7.5 which could be part of the problem by causing a lockout. @memariposaa welcome to the forum!

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Thanks! If this is the case are the nutrients I got enough? On the side it say “4mL per liter during all weeks of the grow phase”, “2 mL per liter for small plants with 3 to 4 sets of leaves.” I gave them 2 mL in one liter for the first time today. How often should I supply them with this mix?

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I would slowly bump the dose up and lower the water to a pH of 5.6 to 5.8 to see how the plants take to them. I would also suggest checking pH and PPM’s of your feed, water to run off and recheck the runoff pH and PPM’s. I have never grown in bags so I really don’t have a good answer for you about feeding schedules. If you can get some Recharge, UC Root or Atomic Root Powder to help with flushing it will help you in the long game. @sssportsmfg, @happilyretired, @PreyBird1 would probably be a better source of information for growing in fabric pots. @TheMadFlascher is a great source of information on plants also.

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Is this your soil?

I would guess your soil is hot. Just need ph’ed watering.

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My soil is this: For indoor & outdoor plants “Grow Plus” – Anagnostou – Production and Packaging of Soils, Compost and Substrates
ph’ed watering you mean lower ph in my water? Like @nacho151 suggested?

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Im not a huge fan of fabric pots. I like grow bags. They drain better and hold moisture in better for me. I suspect the plants arent draining properly and has unsed nutrients and is wet in the root zone.

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Your soil has nutrients. It could have just b3en watered for the first 3 to 4 weeks and then light to normal feed from there.

Give them some water ph at 5.8 to 6. About 2 weeks or less, till you see them pulling out of the yellowing. Getting green and taller.

They are in a bit of shock from to much food. That would be my theory.

You have a pic of them in normal light?

A pic of the soils nutrients content?

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I should have taken normal light images to begin with…
I excluded one plant that seems to be doing best.
Soils nutrients content it says on the back “Rich in nitrogen, phosphorus, potassium and trace elements”
I included a photo of my ph-meter, it reads at about 7-8. I also putted it in a glass of water it reads about the same but closer to 7. I haven’t tested it in water including my nutrients.








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You probably should use these type meters to check your water before giving any to your plants, I would suggest Hanna instruments though if you can afford them.

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Here is another couple of articles that might be worth the read for you.

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I just remembered I had some photos from the first or second week. Leaves on two plants were not looking good at all. I don’t know if it helps or gives a definite sign for a problem…





@nacho151 @Slym3r @PreyBird1 @Skinnyhb

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Well under regular light your plants look like they can recover easily. I’m thinking a good flush like @Slym3r suggested would help you a lot. That soil is pretty hot and isn’t really formulated for cannabis IMHO. Something I learned quickly is soil can adjust your pH and not always in a good way. Cannabis plants like acidic soil pH’ed between 5.5 to 6.5. Tomatoes and flowers like it closer to the pH levels at 6.5 to 7.0.

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The easiest thing to do first would be to figure out where you’re at rather than throwing things at it.
your plants are big enough where they can handle hot soil besides the fact is I’m not seeing burn tips on most . This leans towards pH problem especially since the label says how high it is. If it were me the first thing I would do is get a pH meter and check the water you’ve been using to see what the pH is before you start. Then water your plant enough to where you get a cup or so of runoff and check the pH. This will tell you what the pH is in the room zone. Once that is done then you can PH your water above or below where it is at now and water it’s very heavy to correct the pH in the root zone.

You’re getting a lot of suggestions here, so I would suggest picking whichever person you feel comfortable working with and private message them. This way you get one on one help and prevent you from trying to fix too many things at once. :+1:t3:

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I’m just gonna throw in what I haven’t seen anyone else mention, and that is you are trying to grow small plants in veg under a flower cycle light, and an extremely low K flower light to boot. It has virtually no blue, green or yellow. The sun doesn’t put out light like that.

Marty

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You never grown with hps?

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@Slym3r No, it is my first grow

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