The Gourami is another bigger family of fishes. There are many different versions of this species, that most work well in freshwater indoor aquariums. If you plan to buy some of these, depending on the type of Gourami you buy, you’ll need a bigger or smaller aquarium. For instance, the Dwarf Gourami, is a small version, that will live happily in a 10-gallon water tank. But there are others, that grow way bigger, and could need an even 30 or 40 gallon tank. Something common with all Gouramis, is the fact that they like a well-planted aquarium. So, make sure your tank is full of tall plants, that touch the surface of the water. This will make them feel at home. Also, keep in mind that males don’t like each other; they quickly become aggressive towards one another. So, keep only one male in the tank, with multiple females.