Originally Posted by Srkdvmmom
Called the store where I got it.
It is Taiwan Green Lotus apparently. Though I cannot find anything on that either.
That narrows it down. The commonly-called "lotus" plants more common in aquaria are in the genus Nymphaea, also sometimes commonly called lilies. We have the common Red Tiger Lotus, Nymphaea lotus, in our profiles, and it has a green form; the leaves of this species are more elongate. As they are with most of the other species I know of.
However, I did find a "lotus" plant referred to by one writer as Nymphoides sp. "Taiwan" that might be it. The leaves are round and sharply indented at the base. This genus has several species, one of which is our Banana plant, N. aquatica that we were thinking of earlier. It is in Kasselmann's book, my standard reference work, but at the end so I missed it earlier. She says this species is still unidentified (not scientifically described), and nothing is known of its natural habitat. It was first imported from Taiwan, hence its name, in 1994 by the Aquatic Plant Nursery Dennerle. Dr. Kasselmann writes that she has been cultivating this plant for many years; surface-floating leaves, common in other species in this genus, have never been produced, nor has it yet flowered [at least at the time of her book, 2003]. She calls it undemanding, very fast-growing; leaves reach to the surface but floating leaves are not produced.
On one of my plant groups i have come across photos of this plant, and even a flower. The species has so far still not been described. Photos below; the tall green plant is this species.