They are a true freshwater puffer as said.

They prefer fast flowing water, but as far as puffers go are relatively undemanding when it comes to water parameters. They will do well in a wide range of pH and have a stronger tolerance for dirtier water.
They need groups to thrive, 3 at the minimum but the more the merrier, as they are naturally skittish and nervous fish.
Like all puffers, they need plenty of meaty and hard shelled foods to keep their beaks well trimmed, but it’s almost always inevitable that you have to manually cut their teeth.

These guys seem to have a very fast metabolism, and would benefit from at least daily feedings, if not multiple small meals per day. With any puffer, breeding your own live foods (shrimp, scuds, snails, etc.) will help.
They are very peaceful for a puffer and most tankmates will cause more harm to the Amazon than the other way around - smaller high bodied tetras, Cory cats, livebearers, and plecos, all would make good tankmates.

I kept mine with serpae tetras, skunk/sun loaches (I don’t recommend as they are also snail eaters, but they were leftover from when the tank was an mbuna tank), a bn pleco, and some mollies.