
Splashing Tetra
Copella arnoldi
- Care level
- Intermediate
- Adult size
- 5.5 cm
- Minimum tank
- 81 litres
- Temperature
- 20–28 °C
Species profile
Mimagoniates microlepis
Common names: Small Scaled Tetra, Blue Tetra

A slim blue tetra from cool streams in Brazil, also called the Blue Tetra, and it prefers cooler water than most. Keep a group of at least 6 in 87 litres or more.
A slim blue tetra from cool streams in Brazil, also called the Blue Tetra, and it prefers cooler water than most. It is scarce, but calmer than the fish more often sold under that name.
Check the scientific name when buying, as common names vary between sellers and countries.
Mature females are usually rounder in the belly, and males are usually slimmer and often brighter.
A long tank with open swimming water, plants around the edges and steady filtration suits this fish. A darker substrate and some floating plants usually bring out its colour.
Active and social, and most settled when kept with its own kind.
Keep a group of at least 6, and more if you can. Larger groups are calmer and show better colour and behaviour.
Not territorial, although males may spar and display.
Suits a community of similar-sized, peaceful fish that like the same water. Avoid large predators, which will treat it as food. It may eat baby shrimp.
Keep the pH steady, because this fish is sensitive to swings. This fish prefers cooler water than most tropical fish, and it may not need a heater in a warm room.
A surface-feeding insect eater from fast streams. Offer floating flake and small insects such as fruit flies and mosquito larvae.
Feed small amounts, and remove anything left after a few minutes.
An egg scatterer with no parental care. Adults eat eggs and fry, so use a separate tank with fine plants, moss or mesh on the bottom, and remove the adults after spawning. The fry need very small foods at first.
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