Nitrogen deficiency? Nutrient lockout? Help pls!

Kassiopeija said:

The pH 5 feeds are causing me a headache. Especially since I have no clue if he did really soak these pots completely full with pH 5.0 water full or just did add half a cup to these pots...?
I also feel he's not watering correctly, and that is a huge can of worms on soil, esp. with small plants under somewhat weak lights...

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The ph 5 irrigation was 250 ml. I've read from many sources that the amount of water of 1/4 of the pot's capacity is for when the plant is bigger, not at this stage. The way I water is pouring small amounts and waiting for the substrate to absorb. Normally I point halfway between the stem and the border of the pot, making sure that all of the surface gets moist. With this 250ml amount, i normally get a little runoff after a few minutes.

BTW @OP
as for your light's ppfd - it's ok if you grow forself but don't expect huge colas - rule of thumb for Cannabis in flower is 700-1000ppfd. But your ~500 are going to work as well, you'll see.

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Yeah, i've read that 700-1000 is the ideal for huge colas, but as i'm growing to smoke myself and didn't have more money to spend on lights, thought this would work. Thanks for the advice.

descon0c1do said:

The ph 5 irrigation was 250 ml. I've read from many sources that the amount of water of 1/4 of the pot's capacity is

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correct

descon0c1do said:

for when the plant is bigger, not at this stage.

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incorrect - you water the soil, not the plant.
So whenever you water, all soil needs to be moist - beware of dry spots.

just to illustrate an example, if you water only 500ml, then all roots which wouldn't see water for an extended period, will wither and die - only moisture can prevent this.

descon0c1do said:

Yeah, i've read that 700-1000 is the ideal for huge colas, but as i'm growing to smoke myself and didn't have more money to spend on lights, thought this would work. Thanks for the advice.

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it'll do - you also may have some of your other bulbs to cover the corners...?

myke said:

What I don’t understand is he said he’s vegan. Won’t add organic fish fertilizer? But phosphoric acid is ok ?

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well.. phosphoric acid is taken from rocks and "organic fish fertilizer" is made from dead fish, isn't it? one doesn't kill animals, the other one does.

UPDATE!

Following the idea that the plants might have a nutrient lockout, yesterday I watered 1.1 lts to each pot with pH 6.5 water only. When I measured the runoff EC, it was really high, many around 2.1 and a few going even to 2.3/2.6. So, apparently I had a nutrient lockout going on.

I did a root wash until the EC was lowered to 0.7 in all the pots with pH 6.5 water. Applying 1 lt at a time, giving 4 minutes for the runoff and measuring ec with each liter. 5 lts total to each pot until they reached EC 0.7.

Apparently, the problem is that the substrate is too strong for putting clones of the size they were when I transplanted. I came to this conclusion because I didn't add more than the mychorrizae and the NPK+, that as it is organic, almost doesn't change the EC: pure water is 0.114 and when I add the fertilizer it goes up only to 0.145, which is pretty much nothing.

Any thoughts/ideas on how to continue?

Will I have to start giving it NPK+ un the next watering right after the substrate dries?

Do you think this will affect the plants production immensely?

I wouldn't like to let these go. The clones were a gift from a friend, they come from a mother he has. And on the other side, it's not easy here to get seeds to start a new crop. Ordering by mail is quite risky because as we have a special tax regime on the island, everything that comes this way goes through customs.

Thanks in advance for your help.