Is this leaf Septoria on my young plant or why there are yellow dots?

[PUXYPAN]

First of all hello stoners ^^
I do use medical weed for quite some time and its the first time for me that ime growing on my own.
Ive read quite a lot about this whole topic, still i miss practical experience.

The Problem is, my 3 1/2 week old Plant does look a lil bit unhealthy on its first leaves.

I first thought it might be a nutrient burn, but i cant imagine it since my conductivity meter shows low values.
Leaf Septoria also does seem unrealistic for me since i do not have any other plants or even mould in the growroom, or rooms attached to it.
Do i need to worry or is this normal for a plant at this age? Ime thankful for any help regarding this.

Here some topical data:
|-Growroom
|Type: Indoor,closed, 16cm², light ventilation
|Temperature: 21°C Δ
|Humidity: 42% Δ
|CO2: 700-1050ppm (900ppm Δ)
|TVOC: 190-300ppb (235ppb Δ)
|Pot: Plant fiber ~0.4L # Temporary, will put it in a bigger pot soon

|-Plant
|Strain: Royal Jack Automatic (Jack Herer x Ruderalis from RQS)
|Type: Female, Seedless, Autoflowering
|Growtime: 9-10 Weeks
|Flowering phase: 6-7 Weeks
|Climate: Mild
|Planted: 20.2.20

|-Soil
|Soil: Cactus soil #Not ideal i know, still it should contain most needed nutrients or?
|Fertilizer: 'Green house powder feeding grow' in low concentration
|Soil fertility: 220µS/cm Δ # A bit low, is it okay for the start?
|Top Layer: Clay granules

|-Light
|Type: LED
|Wattage: 150W
|Distance: 15-20cm
|Wavelenght: Mixed(1/1/1/1) 650-660nm, 620-630nm, 430-440nm, 450-460nm #I hope this is acceptable, other lamp types are pretty expensive
|Efficient light intensity: ~15k lux # Could be more, the luxmeter isent calibrated for leds
|Light Cycle: 18/6

|-Water
|pH: 8.0 +-0.1 #I know this is a lil bit too high, any tips how to lower it?
|Water Cycle: All 3 Days, when ~15% moisture is reached
|Soil Moisture: After watering at 40% Δ

I hope this isent too much data, i just wanted to track everything properly to achieve a good yield.
Thanks for reading and helping me with my stuff

 

[Cannadian420]

It is my understanding that while growing in soil it's best to ph at 5.5-6 during veg and 6 - 6.5 during flower.
I'd fix the ph first because we know it's off. I've read about people using lemon juice to lower ph but I use ph down I bought it Walmart or Canadian Tire, not sure. You find it anywhere these days though.

 

[PUXYPAN]

@Cannadian420
Ty, ill start of with lemon concentrate, most ph down products from my local mall are for pools, so idk what else is in there.
Any recommendations for an simple Ph tester?

 

[Cannadian420]

@Cannadian420
Ty, ill start of with lemon concentrate, most ph down products from my local mall are for pools, so idk what else is in there.
Any recommendations for an simple Ph tester?

I use a simple ph test kit like this one

General Hydroponics PH Test Kit, 1-Ounce : Amazon.ca: Industrial & Scientific

General Hydroponics PH Test Kit, 1-Ounce : Amazon.ca: Industrial & Scientific

www.amazon.ca

 

[PUXYPAN]

So ime feeding my plant 6.3~ph water now, still it seems to go worse.
From the optical look it may be a nutrient deficiency, it may be potassium but ime not so sure.
Since i have watered with high ph water before, it may could also be zinc or iron since these are not available to the plant if the soil ph is too high.
I cant imagine that but do you think a distance of 10cm is too close to the plant? The temp is okay, and my LED only takes 25W.
What do you think? Do i need to be more patient or should i get some fresh soil?

 

[BubbleBucketz]

Damaged leaves wont recover. Look to new growth to see if the problem is fixed.

 

[BubbleBucketz]

Keep the PH in the 6.3-6.5 range for the entire grow. Also allow the soil to dry out a little between waterings. Young plants dont need much. Do you have cal-mag?

 

[Cannadian420]

Yeah, I water at 6.5 through the entire grow give or take a point or two. I wouldn't worry about the light raise a little to ease your mind if you'd like. Those damaged leaves are like for ever now. The new growth will tell the tail for you. Send some photos of the plants to compare to the first ones you posted.

 

[SmokingWings]

The Problem is, my 3 1/2 week old Plant does look a lil bit unhealthy on its first leaves.

I first thought it might be a nutrient burn, but i cant imagine it since my conductivity meter shows low values.
Leaf Septoria also does seem unrealistic for me since i do not have any other plants or even mould in the growroom, or rooms attached to it.
Do i need to worry or is this normal for a plant at this age? Ime thankful for any help regarding this.

.....<snipped>>>

|-Soil
|Soil: Cactus soil #Not ideal i know, still it should contain most needed nutrients or?
|Fertilizer: 'Green house powder feeding grow' in low concentration
|Soil fertility: 220µS/cm Δ # A bit low, is it okay for the start?
|Top Layer: Clay granules
........<snipped>>>
I hope this isent too much data, i just wanted to track everything properly to achieve a good yield.
Thanks for reading and helping me with my stuff

People are going to need to know your soil type and it is good that you mentioned it in the first message. Cactus soil is not good for this type of plant. You will have to transplant these into a good soil soon, the sooner the better.

Since it looks like you choose an auto-flower strain you might want to consider one of the "water only" soils sold in most grow and garden shops. You can transplant into that the same day you buy it. It will reduce the number of problems you might run into. Plus, the sooner you transplant should help with the learning curve.

Try to avoid any soil that says "Timed Release" on the package. This is not the same as a soil that has slow release organic materials added.

Then about a month before you start the next grow you could mix up your own soil . This gives it time to age which some gardener and growers call "allowing the soil to cook and cool off".

I think that many in the group will suggest transplanting out of the cactus soil as soon as you can.

Good luck.

 

[BubbleBucketz]

Fox Farms is a very common soil used. Fairly cheap and you can get through a good portion of your grow without needing to feed.

 

[PUXYPAN]

Thanks for all ya help.
Since ive adjusted the pH, everything has been going a lot better, take a look ^^

The only thing ime wondered about is the size. The harvest time is around 9-10 weeks after planting, now it is 10 weeks after planting but the development of the buds leaves much to be desired.
The flowering phase started 3 weeks ago, do you think that due to the pH problems at the beginning, the overall grow time may be delayed? The plant actually should have a flowering phase of 6-7 weeks.

 

[Cannadian420]

I'd say that's just an auto for ya. You win some, you lose some. Autos are very unpredictable. The times are just suggestions or it "may" take that long. Just grow em till the trichromes are mature.

 

[SmokingWings]

Thanks for all ya help.
Since ive adjusted the pH, everything has been going a lot better, take a look ^^

The only thing ime wondered about is the size. The harvest time is around 9-10 weeks after planting, now it is 10 weeks after planting but the development of the buds leaves much to be desired.
The flowering phase started 3 weeks ago, do you think that due to the pH problems at the beginning, the overall grow time may be delayed? The plant actually should have a flowering phase of 6-7 weeks.

What @Cannadian420 mentions about autoflowers and that sometimes the grower wins and sometimes does not. I also like to think that with experience there will be improvements in size, quantity and quality. A saying is "...grow for quality and the quantity will follow on its own."

 

[Cannadian420]

What @Cannadian420 mentions about autoflowers and that sometimes the grower wins and sometimes does not. I also like to think that with experience there will be improvements in size, quantity and quality. A saying is "...grow for quality and the quantity will follow on its own."

For sure. Some autos don't have enough recovery time when stuff goes south. I've also seen some autos that handled alot of abuse and turned out great. This is not to say that these genetics are bad. Grow the same seeds again and from what he's learned they most definitely will yield more.