The silver dollar is a peaceful schooling species that spends most of its time in the mid- to upper-level of the water.
Compatibility to other fishes
The silver dollar is listed as semi-aggressive but it is very mellow like the pacu. These fish can be kept in community tanks with fish that can’t fit in their mouths, and once fully grown, they can be kept with larger fish like oscars, pikes, and larger catfish.
All you need to know about Silver Dollar tetras
A medium sized fish which is very lively and so needs more space than its size leads you to believe. As the fish grow they become increasingly wary and are prone to panic if they are startled. They should be kept in a group of at least five individuals, with other small to medium sized peaceful fish which will help to reassure them. Very small fish like tetras may be eaten though. In the wild silver dollars come from areas with dense vegetation, this isn’t possible to replicate in captivity due to their plant eating, but one aspect of dense vegetation is subdued lighting as a result silver dollars are less nervous under dim lighting than in brightly lit tanks. Silver dollars although herbivores are close relatives of the piranha, they have a very powerful bite and relatively strong teeth so be careful when handling large adults.
Silver dollars are herbivores, they will eat all aquatic plants so if you want to include some plants in their aquarium they will have to be artificial. Feeding silver dollars isn’t as straight forward as just using a commercially prepared dried food if they are to remain healthy. Lots of fresh greens must make up the bulk of their diet – lettuce, water cress, blanched spinach, cucumber, skinned processed peas, algae wafers and occasionally live or frozen food once or twice per week. Being herbivores they prefer to constantly graze so feeding should be little and often.