Alternative for Vallisneria

[M.ramirezi]

My problem with the Copella arnoldi is probably because of the lack of plants on the surface.
Unfortunately, floating plants won't survive. Vallisneria might be an option, but I have only some gigantea, and new bought Vallisneria always dies in my tanks.

Does anyone have a good alternative for Vallisneria?
I have weak lighting:

(changed the tank setup yesterday, the Nymphoides has moved to my other tank, and I have quite some open space at the surface now)

Distribution isn't important for me, although a South-American plant would be nice
Temperature: 27/28°C
pH: 6 - 6,5
GH: 4 - 5

 

[Jonathan Aquair]

I'd go with Cryptocoryne Crispatula var. Balansae or C. Retrospiralis.

 

[M.ramirezi]

Thanks, I'll have a look if it's not to hard to get over here.

 

[gerald]

Guppy-grass, Najas guadalupensis - either free-floating or rooted.

 

[DaRe]

Crinum thaianum perhaps?