I started out keeping a small school of harlequin rasboras as dither fish for my clown loaches, together with a few rainbowfish and corydoras, and over time we've become very attached to the rasboras. They're the smallest fish in the tank, so I'm careful to make sure that the rainbows don't gobble up all the food before the rasboras can eat, but apart from this they get along famously with the other fish, and I've found the rasboras to be hardy, friendly, colorful, and easy to keep.
I have been keeping four Harlequin Rasboras in my aquarium for about a year, two females and two males. Peaceful and social fish, they love to school, especially in the mid-range of the tank. The females tend to be larger and have more curve in their bellies and backs, as well as the black triangle on their sides. The males are straighter in back, belly, and triangle. One of my females tends to enjoy chasing the others around, but no fights occur and, according to my view, it's all in good nature. If you keep Harlequin Rasboras, they will soon learn to expect food every time you come near the aquarium, and they swim up to the surface to greet you! They are precise eaters that are very good at consuming sinking food before it hits the bottom where they can overlook it. However, don't feed them food with too large a grain, because it can get stuck in their relatively small mouths. You can easily accentuate their striking red color by including tall green plants, real or artificial, in your aquarium. Hardy, easy to keep, and very handsome, Harlequin Rasboras are a perfect choice for the beginner and expert alike.
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