top leaves curling down suddenly

hey guys,
so my cinderella jack sprouted during last days of July, grew up very green and bushy with leaves pointing upwards till lately, been nearly 2 weeks now that these top leaves are twisting and getting me worried, and im struggling to know what's the prob. took pics of some other strains Im running next to it : lemon kix (as big as the cinderella), strwb cheesecake and wtrmln skittelz still in the veg phase as u can see.. all of these 3 not showing any curling issues, just the cinderella..

soil : hydroponic pebbles under, canna terra pro plus then a layer of pebbles on the top..
light: Mars hydro ts 1000 + another cheap 600w led panel bought from amazon
nutrients : Biobizz grow/bloom, plagron fish force, bat guano (one big spoon spread around the soil during 2 week of veg)

so all the plants are getting watered and fed the same.. why the curling for only one of them ?

thanks for your help guys

Umm Cramped spaces

Budzbuddha said:

Umm Cramped spaces

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indeed but is it a factor for this type of curling ?

Is there air flow thru them ? - they need good air exchange.

iAwin said:

indeed but is it a factor for this type of curling ?

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It looks like a small 2x2 tent. Is there any reason for putting two lights in there?

Budzbuddha said:

Is there air flow thru them ? - they need good air exchange.

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extractor + fan and bottom small windows open.. and both plants are enough lollipopped to let the air flow perfectly from under ..

twentyeight.threefive said:

It looks like a small 2x2 tent. Is there any reason for putting two lights in there?

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not any special reason tbh.. why ? haven't had any issues related to it before this grow.. instead ive got some huge buds ever since ive added the ts1000..

iAwin said:

not any special reason tbh.. why ? haven't had any issues related to it before this grow.. instead ive got some huge buds ever since ive added the ts1000..

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Looks like too much light. But it’d be impossible to determine without more info and pictures with the grow lights off.

twentyeight.threefive said:

Looks like too much light. But it’d be impossible to determine without more info and pictures with the grow lights off.

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Roger that, I'll take some asap in day light tomorrow morning

twentyeight.threefive said:

Looks like too much light. But it’d be impossible to determine without more info and pictures with the grow lights off.

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are these ok or should I take it out from the box ?

iAwin said:

are these ok or should I take it out from the box ?

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They look like a nice healthy green. What are your temp and RH like?

iAwin said:

are these ok or should I take it out from the box ?

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Move your fan(s).

RH between 40 and 50 goes up to 60 for few hours when I just water them and the temp between 26-30... but the thermometer is standing on the pebbles so maybe its a lil hotter on the top..