Morning update...
Tank water test results with JBL strips:
NO3 = 10 ppm
NO2 = 0 ppm
GH = 4 - 7 degrees
KH = 0 degrees
pH = 6.4 (or lower?)
Cl2 = 0 ppm
Tank water test results with Aqua are Master Test Kit:
NO3 = 5 - 10 ppm (very weak, but progressively growing)
NO2 = 0 ppm
NH3 = 0 ppm
KH = 0 degrees
pH = 6.0 - 6.5 (or lower?)
PO4 - P = 0 - 0.25 ppm (starting to show a very weak yellow color, depending on background and light)
Tap water looks exactly the same as before with a strip, although the pH seems a bit higher today (6.4 - 6.8) and with a touch of chlorine (0.8 - 1.5 ppm).
On another topic, one of the plants I got seems to be quite happy. I splitted the pot into 4 bits, and although all of them are growing, two of the stems are thriving, throwing roots everywhere. If anyone knows the species, please do let me know!
@jamiep, any chance you could know it? You got the other one right.