Onion plant?

Search under Crinum for the larger species; under Zephrantes for the small species. The Crinums are heavy feeders and like moderate to high light. Most will shade other plants due to their very long leaves which float just below the surface. The Zephrantes are a but less demanding, look a bit like a very heavy-bladed hairgrass.
 
I have had one for about two weeks now in a 29 gallons tank with 38 watts of lighting. Have no idea what species it is though. My substrate is all gravel, but my LFS sold me this product called ROOT. It is a German product that he told me to pour into my tank and mix around into the gravel. He told me that it's what they use in their planet tanks. I put this in one week before I got my plants. Now that I have live plants the only thing I do it is add Flourish Excel every other day. It seems to be doing just fine. If you do get one do not bury the bulb.
 
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