50g Amazon species tank

So what about plants? And substrate? I want to try and keep it as realistic as possible. I have a vague idea of what I'd like it to look like. I want it to be really well planted and be as much about the plants as the fish.

Here's a link to info on plants of different regions. Not much for South America, though. And not many of those are on the easy list! But it might help.

http://www.plantgeek.net/plantguide_cat.php?category=6

A 50 gallon would be nice for a pair of angels. Cories are also South American, they'd fit right in with some of the larger tetras. Angels look great swimming between tall plants.
 
I am not sold on the fact that a 50 gal is too small for a trio of discus. The issue will be getting compatible ones. If just juvies they will more likely get along and will not over stock the tank even with some dithers and cory for the bottom. You will have to keep up on the water changes though.
 
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