[Peter Finke]

Yankadi, all the species you mention are hitherto not being cultured well in a submersed, but only in an emersed mode (with the leaves growing outside of the water in heavily moist air); in a substrate composed from old beech- and oakleaves, as you say. You should tell us whether your way to care for them in plastic bags is emerse too, or submerse. I know nobody in the whole world who is capable to grow these species submersely in aquaria today. Every progress in this direction would be of great interest, but it is not very likely.
There is no var. “didencis”; the right name is var. diderici.