Looks alot like Hygrophilia corymbosa. I have the compact form of this plant, looks exactly the same as yours, colour and all. Only difference, the leaves on mine are not quite as long as yours. Think you might have the larger version.
90 gallon, Crypt undulata "broad leaf" Lobelia cardinalis small and large form. H.corymbosa "compact" Crypt parva, Crypt Red Wendetti Downoi, Bacopa, Samolus Valerandi, Limnophilla Aromatica Alternanthera Reineckii lilacina(purple)
2x 150 Wt 10000k HQI Metal Halide, 2x 65 Wt 6700k-Colourmax