Ok- here's the deal with big-chain petstores aquatic plants. As long as the plant can survive in water for about two-three months, then it is deemed "aquatic." ESPECIALLY if it is a cheep plant that they can pawn off. Most of the time the people in charge who sell them don't have a clue that they arn't true aquatic plants, and so they get put in with the other stuff.
Dwarf mondo grass is an amazing ground cover for filling in the front garden beds of houses- it is very short, EVERGREEN *cheers*, bears small flowers and tiny berries, is not invasive, easy to eradicate if need be, and amazingly durable. It can be used for light foot traffic and never needs a pruning. Oh- and it can grow in areas too shady for grass to grow. It has tuborous roots that allow it to survive short droughts and dry summers, but can also fair well in constantly damp areas. It will grow faster (though it grows relatively slow in good soil) if planted in well-draining loam (what plant doesn't? lol. Don't answer- that's a joke among gardeng folks...).
Oh- and there is also a color morph called black mondo grass (very original name, eh?). It is a deep purple/red/green color. Kind of interesting, but I'd rather have green.
black dwarf mondo
I'd say try it- and if you find it starts to yellow too much then take it out and plant it in your garden or use it for a shallow-bowl house plant. Either way it is a fantastic plant and will always have a place in my gardens because of its beautiful and pleasing characteristics.
It does have a clumping/colonizing habit, so if it fairs well you may want to split it every year or two after the plant has become established. When the plants have been in one place for five years or so then they tend to look as if they are growing on top of each other. Here are some pictures of gardens/etc of where mondo grass has been a great addition:
patio patterning
DMG with berries
DMG showing berry and root tubers- these havn't had need to store water apparently- they are not thick like they are in my plants that are planted in the dry areas of my garden
Grass replacement
big list of ground covers
Other than that, moneywort (Lysimachia nummularia, or Lysimachia nummularia 'Aurea'
is a nice one) might be a nice choice...
and this link may give you more ideas:
groundcovers
Or you could just go to a pond and look around the edges, take a couple snippings of some "weeds" and try them out- you'll probably have to do a lot of trimming
-Dazz