Vigorous, Medium Light Plants

[mantella]

What are some fast growing, almost tank choking, plants that thrive in moderate lighting? Also, ideally they'd be large enough to fill the water column of a standard 10 gallon.

 

[Ninjouzata]

Anacharis/elodea and watersprite are what first comes to mind.
Dwarf water lettuce is a floating plant that can really fill in the top of the tank as well and when the roots get long if you leave them be you won't be able to see the back of the tank.

 

[FoundMoney]

I've found cabomba to be very growing in medium light with trace dosing.  It's one of the only plants that I've had to trim regularly because it was overgrowing.  However, in moderate light without CO2 it tends to break up more and can be messy.  Even with higher light and injected CO2 it can still break up some, but not as much.

 

[BenVernon]

Dwarf Sagittarius does great under moderate lighting and will grow extremely fast (mine grew an inch every 2 weeks). It can grow up to 16 inches providing that there is plenty of CO2 (or should I say 'planty'!).