Looking for Plant Suggestions

I have a 20 gal long, lit and heated, freshwater aquarium. In it I
have 1 dwarf blue gourami, 6 zebra danios, 7 neon tetras, and two
oto's. I've had a variety of plants but none of them seem to do well.
I've had something that looks like christmas tree branches, foxtail,
moneywart and wisteria. Right now the only thing still alive is the
wisteria. The moneywart I've replaced a couple of times because the
fish seem to enjoy eating them.

The question is, what can I do to keep my plants alive.

Also I have a 5 gallon, heated filtered plant for my betta. It, unlike
the other plant does not have a light, although it sit's under a
standard room torchier. Right now I have a few silk plants but I would
like to add some real plants.

Thanks,
Klane