First grow ever, and it's DWC

Here we are guys in the third week of the journal, last week I had some concern about the ph which was spiking at 7+ overnight but the problem solved it self when the roots started to shoot in to the water. my other concern was the temp inside the grow box which i solved buying a second hand portable ac (40€! such a bargain) now as you can see the girl is thriving and the roots too!! as you can see in the picture i put a white bed sheet around the black container so the water won't get hot, it works AMAZINGLY now the water goes in the hotter day at max 21.2 and than goes back to 20. Day 20 hey guys a small update, yesterday i topped the girl, i have only one concern, the plant is so damn bushy and the lower side shoots are almost covering the shoots on the the side of the topping. looking close i thought that maybe I had to top one set of leaves lower because under the fan leaves she is really really bushing everything is exploding but the plant still quite short, 7cm (2.7 inches) is that ok? apart from this i can't complain, the dwc system is working amazingly and the pland is healthy. please feel free to give suggestion comments or critics love you all I think the plant looks a bit bit pale so as I am writing this i added a 0.5 ml of flora micro to the res to add nitrogen, we will see how she reacts in the next days. In the next days I will top her and start some lst