Hehe, thanks for posting guys.

The yellow leaves started to appear when these plants were much younger, I was paranoid with watering and they started to dehydrate. Since then I have eliminated my paranoia and I'm watering them well. Their leaf color is healthy greenish, so I suppose they have enough N. Today I've worked a bit with my ventilation and got the constant temp. down to 25c. What I still have to do is make the walls white, so less of the precious light is wasted. Also, I need to close all the extra holes where unwanted light is coming in. I'm starting to slowly prepare for flowering stage.
I've been very careful with adding nutes so far, I'm adding them once a week, a weak macro+micro element solution. For flowering I have prepared some additional Phosphorus 18% which can be "melted" in the water. For watering I use rain water only.

I'm really happy that I am not the only one posting in this log, hope you guys like it.