I'm unsure about species as it was given to me by a friend. It does resemble H.vulgaris in appearance but seems to thrive in the heat and I thought vulgaris was a temperate species that did poorly in the heat. My neighbor saw the plant and thought it was edible and was asking for cuttings. HarleyK
According to Kasselmann, the range goes from Europe to Northwastern Africa and a stretch in Iran. It grows up to 28 C. I'm not surprised that it thrives in your tank...