Drooping, folded leaves. Over or underwatering?

Yo, does anyone know what's going on with my plants. They look a little small and they're drooping. I don't think it's overwatering but I've been wrong before. Lights are 600w HPS, tent sits around 25 celcius lights on and about 60% humidity. Light distance is now 18 inches. Just looking for some general feedback so I know what sort of thing might be wrong. It really looks like overwatering or underwatering though so I kinda wanted to know if I should back off or increase frequency

 

If it helps diagnosis here is what they looked like yesterday a couple days after watering.

 

Canna terra plus, so inert soil I guess, and they're about two weeks old now

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I mean I water them once every 3 to 4 days and water til I get a little runoff. They're in little 1l propagation fabric pots so they dry out pretty quick anyway

 

I'll post an update in a day or so and you can see what you think I guess

 

The only reason I watered them today is because they were due a feed, but with that said they were still dust dry a knuckle and a bit down and they felt really light. It'd been 3 days since their last watering. I've also underwatered them pretty badly in the past

 

They looked like that when there were dry, I took those pictures minutes after a feeding

 

It's in a fabric pot that doesnt sit in it's runoff

 

I'm going to leave them to dry out from now and see if they perk up over the course of the week

 

I tried to get some similar pictures from later on today after a watering because they look more perky to me. I have no idea though, honestly.
Before:

After:

 

Could it be underwatering and the fact that I took pictures after a watering made the leaves look swollen without really perking up? I don't really know how quickly they'd react to things like that