Do anyone know what might this be? I will add pict...

Actually what you are seeing is quite common: it's nute burn. You mention you are using fertilized quality soil, that means that the soil already has a lot of nutrients in it and on top of that you added more nutes. Alg-a-mic won't burn the plants since it barely rises the EC/PPM of any solution, but Biogrow can be quite strong n young plants. I use Biobizz too so I know quite well the concentration of the product you are using. 2 ml/lt of Biogrow has a concentration of 0.6EC (300 PPM) and assuming you are using regular tap water, that usually has a salt concentration of 0.4EC (200 PPM), that means that you are most probably feeding at a strength of 1 EC (500 PPM). I've had young plants burn at less than half that strength when they are in pre fertilized soil. 11 liter of fertilized soil, lasts me 8 weeks without needing nutes, and you are using a 20 liter pot, you should not need any nutes for the whole grow, or maybe a tiny wee bit at the peak of flower, but not at this stage. Do a flush and stop any feeding. Also sometimes too high pH of water can lead to weird leaves symptoms like them curling upwards like a taco, it has happened to me too; there could be some of that too.

Gotta love those taco leaves...usually either extreme high(or low humidity), heat stress from high heat( I see your day and night temps are very close, there's usually a 5-10 degree change cooler at night, also over watering can cause this too. I see you've got the 300 HID which I think can generate a good amount of heat? I'm sorry for your loss...I love the thought of a wild woods guerilla grow though. Ha imagine the plants just popping up in the wild like that!

Hi This looks like the result of excessive heat, root problems (possibly from overwatering) and/or suffering from extreme humidity levels (such as very high or low humidity).