Problem Curly Leaves on a Plant

Hi everyone, I'm having a little problem surely because of my ignorance growing indoor. I'm growing 4 Mango Sapphire by HSO in a 120x120x180 grow tent, under a 600w HPS supplied by an electronic dimmerable ballast. It's the 4th week of veg and one of my plant is having an issue. I've been watering every 3/4 days giving them BIOCanna nutriments every time until last week when I stopped giving them ferts and continued watering with tap water only correcting pH and bringing it at 6,5. I planted them first in a 2L pot with BioBizz Light soil and then transplanted them in 11L pots. Today I defoliated to permit smaller branches to grow bigger (but that's not the problem).
Leaves on a plant are curlying down, can you please help me?

What is your light distance? can you hold your hand comfortably where the top is for a minute or more, at a glance looks like alsace reaction to heat

What is the temp and RH in there?

mrpuffins said:

What is your light distance? can you hold your hand comfortably where the top is for a minute or more, at a glance looks like alsace reaction to heat

What is the temp and RH in there?

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The distance is 50cm, now I moved the lamp at 70. At 50 the hand was comfortable, there weren't problem, I could stay there for minutes. The thermometer is positioned on top of the extractor to not be influenced by the light. There the temperature is 28/29 C and RH is 40/50%.

Doesn't sound bad for the tempspace, and light, although some can be sensitive.

Prob looking at the watering or nute intake with PH maybe. why keeping PH so high? could hypothesize they need a lower PH level to better take in nutes and perk up.

mrpuffins said:

Doesn't sound bad for the tempspace, and light, although some can be sensitive.

Prob looking at the watering or nute intake with PH maybe. why keeping PH so high? could hypothesize they need a lower PH level to better take in nutes and perk up.

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So, you think PH is too high... I'll try to bring it down and see what will happen. Today they're better then yesterday anyway.

Problem's back... Don't know what to do, some help?

possibly manganese deficiency?

Damn still an issue? any difference noticible right after a watering?

They're like this now. I just fed them with BioCanna products: BioVega 3ml/l (N 3.5%, P 1%, K 5.5%), BioRhyzotonic 0.5 ml/l (N 0.6%, P 0.2%, K 0.6%) BioBoost 3.5 ml/l. I have just switched 12/12

You need mag man epson salt or for a quick fix get water at walmart or local store that has alot of mag-cal in it

FrostFlame said:

They're like this now. I just fed them with BioCanna products: BioVega 3ml/l (N 3.5%, P 1%, K 5.5%), BioRhyzotonic 0.5 ml/l (N 0.6%, P 0.2%, K 0.6%) BioBoost 3.5 ml/l. I have just switched 12/12

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Did you ever figure out what the issue was? I am looking into using biocanna and I seem to read and get a lot of mixed reviews

thats super weird foliage and even weirder how it reverts back to normal then changes again. Id say it has to be something your giving them if it happens after each watering unless im understanding it wrong. I would also say that for soil i PH anywhere from 6.5-6.9 and havent run into any PH problems yet but thats just me.
I would try giving them only one of each product at a time and seeing how they react after getting fed with each one to see which one might be causing this.