Heh, thanks guys, I just spent the last hour and a half trying to ID the thing. ID thread is up in the Planted section. Could be echinodorus quadricostatus but not sure...
Wow, that jar is looking snazzy! I ended up pulling all the hydrocotyle out of my terrariums though. It seems to need a lot more light than I could provide, even in a west facing window, and just bolted up. Not exactly the look I was going for. HC is my new go to lol.