Here are some of the most popular freshwater fish species that are commonly kept in aquariums, each with unique characteristics and care requirements.
A common rule of thumb for how many freshwater fish you can keep in an aquarium is to allow about 1 inch of fish per gallon of water; however, this can vary depending on the specific fish species, their adult size, activity level, and bioload, with heavily planted or densely stocked tanks often needing more filtration and swimming room.
Overview "Gold Piranha" is a trade name for Serrasalmus maculatus, also called the golden mac. The name is sometimes applied to other Serrasalmus species. Widespread in the Amazon, Paraguay and Paraná basins of South America. Grows to about 8 in (21 cm) standard...