Anacharis is a cold water plant so you'd need to acclimate it to the warmer water, I also had the same thing happen until I found that out :)
Plants still need some light to live, although 3.5 feet is rather far...can you get a desktop lamp on it or something?
As for plants:
Java Fern (don't bury the rhizome)
Anubias (there are other types, and don't bury the rhizome)
Anacharis (as stated before)
Myrio (although won't be bright green)
Cabomda (will be darker green)
Water Sprite (grows fast and looks great, can float or bury)
You could also grow some crypts although some of the red plants won't get red without high lighting, but they will still grow. Same with Rotala and Ludwigia although I find Rotala needs higher lighting.
Some liquid fertilizers will help as well, you only have to dose once a week although I split the dose to make it two small meals a week. Works well, I only use API's LeafZone.
Leopards: 1:4 Hawkeye, Luna, Astrael, Dorian, Cullen