I would recommend Anubias and Java Ferns as they aren't very demanding. They can be tied down to driftwood and/or rocks. Depending on how powerful your lights are Amazon Swords and Cryptocoryne would also be an easy plant. Sagittaria and Vallisneria can also be easily used as well. I think plants would work fine with that stock.
What would you recommend for a 330 gallon tank with a stock listing of 1 Arowanna, various Vieja's and some loaches?

