Since I add some CO2 this plant is very difficult to grow :
White leaves and melting (see http://users.compaqnet.be/PLemaire/hetera.jpg)

Parameters :

T 25°C
pH 5.9
KH 3.5
GH 7.5
NO3 36
K 28
PO4 1.5
Ca 41
Mg 8
Fe 0.5

Philippe