The temperature problem is solved now!
When I bought the soil it said it has a ph between 6,5 and 7
I have a PH meter and after watering it shows a PH of 7 so it is not acidic at all

Can it be fert burn after all? Im affraid that the soil has enought ferts in it and since the plants are so young maybe they receive too much

And belive it or not the 11 days arjans haze#3 has very long roots. I have changed the whole soil in the 3 gallon pot and the roots were almost to the bottom

Do you think that only adding distilled water for a week will help plants consume the nutriends on the soil and recover?

And I have a correction to the previous post. It is an INDOOR grow not outdoor