New Grower Day 58 - Yellowing upper/large fan leaves on purple stilton auto

[sunshine1980x]

Hi Guys,

Just a beginner and first auto I've grown. Little bit concerned about the yellowed fan leaves, can anyone offer any advice please?

Problem:
- Upper/Large fan leaves yellowing/dying

Medium/grow method:
- Canvas pots with 2 inch of clay pebbles and coco.

Feed: and supplements used:
- 25ml canna A+B (32ml / 4ml per lt recommended on bottle)
- 20ml cannazym (25ml per 10 lt as per bottle)
- 5ml regen-a-root (cx horticulture) - (8ml / 1ml per lt recommended on bottle)
- 5ml mighty bloom (cx horticulture) - (8ml / 1ml per lt recommended on bottle)
- 5ml head masta (cx horticulture) - (8ml / 1ml per lt recommended on bottle)

- EC 1.7 (calibrated)
- PH 6.0 (calibrated)

Water source:
- 8 litres of water from the tap, left for 24 hours before mixing

Strain/age:
- 58 days from seed. Autoseeds Purple Stilton

Light used:
- Lights on 24/7 from seed
- Fans on 24/7
- 250w hps + 60w cfl

Climate:
- Temps stable around 25-26 deg
- Humidity stable around 38-42

Additional info:
- Running slightly lower feed on everything rather than the recommended amounts
- Bottom feeding every 12 hours approx 800ml with occassional/additional top feed of 200ml. Bottom of canvas pot is dry at 12 hours ... I did leave it for 24 hours one day, but all the leaves had started to droop.

 

[St. Tom]

someone with a lot more knowledge will give you better advice i would remove the damaged leaves off your plant they will never repair then at least you can monitor new growth as from what i can see its only on a couple of leaves the ones dying at the bottom is normal also any reason your running your light 24/7

 

[sunshine1980x]

Thanks for the advice. I'm running 24/7 for ease more than anything because of the temps. If I drop to 20/4, temps will drop to approx 16-18 deg. Not sure if that is ok?

 

[Sour D]

Had a discussion going that lead into my same issue,
https://www.autoflower.org/threads/visual-guide-for-potassium-def.75606/

 

[sunshine1980x]

I 'think' this problem started once I moved onto bloom nutes but cant be 100% certain. I'd say pre-flowers were there for 2 weeks before I added bloom nutes and upped the A+B a bit @ day 46 (12 days ago).

** I did the first week with just head masta, then added mighty bloom approx 6 days ago.

Head masta = N 1, P 2, K 2

Mighty bloom = N 0, P 20, K 22

 

[Bigg Al]

I don't run coco, but are you adding cal/mag with your feed?

 

[sunshine1980x]

no cal/mag in my feed.

 

[St. Tom]

no cal/mag in my feed.

i always run calmag with coco and when i first seen the yellow i thought cal or mag but your girls look lush and green elsewhere and thats why i said remove them leaves and monitor to new growth . also i see your reason is keeping it snug in there to keep the lights on i use a tube heater i dont know if that would work for you as electric bills are sky-high in the uk

 

[sunshine1980x]

thanks, any recommendations on the cal/mag to buy?

re heating costs, I'm only running approx 300w so the extra cost for 4 hours per day is minimal really (£1/£2 per week). I've read various articles re 24/0, 20/4 etc and it seems people have success with both hence why I thought just leave them on (if the plants seem happy).

I've only done one grow before (non-autos) and that was a right headache. I was running approx 700w at one point and heat/humidity was a constant problem. Running at 300 might reduce my yield a bit but its so much easier to deal with.

 

[bakEQuatorial]

Before you buy anything, do you feed nutrients every feed? Do you have water only days? A deficiency is quite unlikely with all the nutrients you give. You can even see some tip burn on healthy leaves. I am guessing a nutrient lockout. Feed only PHed water for a few feeds. Let there be some significant runoff but get rid of it/ don't let it sit. Then ease back into regular feeding but let there be some water only days. My 2 cents.