That's what I was thinking when I read the post. Lots of people bury the little rhizome, make sure if you put it in the substrate, you just bury the "roots" and not the "rhizome" of the plant, otherwise it will surely die! I think I had the worst conditions for java fern and it thrived in my tank and got huge! Root tab fertilizer in the substrate, buried the "roots" only. No liquid ferts and only 30 watts of regular fluorescent lighting (18" flora sun bulbs) over a 44 gallon corner tank! Almost no light at all and it grew really nice. It's a really undemanding plant, you should not be able to kill it unless it's planted with the substrate covering the rhizome IMO.