thank you very much for your prompt reply!

The problem with the guy who "probably" owns these plants is that he doesnt understand english very well...

the temperature is room temperature, about 20-22 C, and they are watered every other day because he "probably" guesses that they dont need every day, the soil is still a litle wet.

The soil is a soil which he "probably" bought from a multistore, no more info on that.

It is "probably" his first try to grow plants, and he doesn't even know the pH of the water or the soil. also, access to pH counters is impossible at the place he lives.

I am sure he is not lazy, he has read and tried to understand the tutorials many times, but he doesnt know very good english! He must have guessed that you could be able to judge from the photos alone.

Thanks again! keep up the good work!