The pH may be high but the water is soft, and hardness is the more important of the two.
There are some 'broad leaf' and 'green' varieties of this plant in my tank. My group of hengeli tend to hang around the amazon sword and driftwood towards the end of the tank. Thanks for the reply its really nice to hear the experiences other people have with this speciesI kept this fish a few times, for many years. I found, and this is weird but not, they liked the presence of Cryptocorynne wendtii. Both hengeli and heteromorpha seemed to want to be under them at times, and would venture out.