Hi, small update: the branch now has some white mold (nothing out of ordinary at this stage), and the tropica soil absorbed all the carbonates in the water, so KH and GH both dropped to 0. Added some kh and some gh solutions, now the values are:
KH: 6 dKH
GH: 10 dGH
PH: 6.5
NO3: 20 mg/l
NO2: 0.5 mg/l
The hemiantus on the front is not 100% happy. I do not know if it's lack of light or lack of nutrients, or just the fact that water had 0 hardness before.. Hope it gets better.
Same is true for the hygrophila on the back, that is losing the lower leafs.
Pogostemon and althernathera both look perfectly healthy.