Leaves curling up - have I overwatered?

[Cap'n Cod]

Hi All

Could anyone tell me what I've done wrong! This is only my 2nd run & I have 2 Sweetseeds Sweet Gelato Auto & 2 Fast Bud Auto #2. I noticed that some leaves on the 2 Sweet Gelato Auto are curling up at the edges (the Fast bud have buckled slightly). The plants are in an insulated grow tent with an oil-filled radiator (it's too cold without, where I live!). I have a humidifier but I don't yet have a hygrometer. They're in 16lt pots and have been for about 2 1/2 weeks. The last twice I gave them each 1 lt room temp distilled water. I'm also on my 2nd week with nutrients (Biobizz biogrow & Activera - 1/2 recommended dose)

Any ideas?

Thanks all & stay safe!

 

[St. Tom]

id say either heat or do you have a fan blowing hard on the leaf

 

[Cap'n Cod]

id say either heat or do you have a fan blowing hard on the leaf

Hello St Tom - I hope you're well! Thanks for responding mate.
No, there's no fan in there, just an extractor. Temperatures are between about 18/19 C unlit & it can vary between 22-25 C lit - although these 2 are closest to the radiator.
But - I have no idea about humidity. When I noticed the curling yesterday, the tent felt REALLY humid, so I switched it off.

 

[bluntz]

I'm with @St. Tom on this one, first thing I would look into is heat.

 

[Cap'n Cod]

Hi Bluntz - thanks!
I might switch positions with the 2 fastbuds, so furthest away from the heater. I'll let you know.
Thanks again

 

[MesaBoogie]

Mine some times do that from light stress. What type and how far are your lights from the plant ?

 

[Cap'n Cod]

Hi MesaBoogie - I've just checked & it's about 30cm (12 in) from the tips of the plant. Is that too close? Thanks for responding, BTW. God I love AFN!

 

[Cap'n Cod]

Right - I've moved the two that were suffering away from the heater & moved the light up to about 40 from the tops. I also started LST (day 18 in soil). I guess wait & see! Thanks for your advice guys

 

[MesaBoogie]

Hi MesaBoogie - I've just checked & it's about 30cm (12 in) from the tips of the plant. Is that too close? Thanks for responding, BTW. God I love AFN!

It depends what kind of light and how strong it is. Did the light come with a par map or can you find a grow journal with the same light to see what they did ? I can just see the bottom of the hood in your pic, it's definitely something I'm not familiar with.

BTW your girls are looking pretty good on day 18!

 

[Cap'n Cod]

Hi It depends what kind of light and how strong it is. Did the light come with a par map or can you find a grow journal with the same light to see what they did ? I can just see the bottom of the hood in your pic, it's definitely something I'm not familiar with.

BTW your girls are looking pretty good on day 18!

Hi Mesa Boogie - thanks again for taking the time (& for the compliment!)
For the light - oh god, I knew you were going to ask me that! It's an LED that I bought with the tent etc for my 1st grow. There's no name on it & I think it's 75 Watts - I was told it would cover a 60cm x 60cm area & it seems to be doing that! More than that, I can't say. I can adjust the intensity, so I'll monitor them & see about turning it down a little. Have a good one!