CHARACTERISTICS
| Synonyms | None |
| Distribution | Brazil |
| Sexual Dimorphism | Male fish have a blue adipose fin, whereas that of the female is red-orange. Mature males also tend to be more colourful and of slimmer build. |
| Maximum Size | 4cm (1.6”) |
| Water Parameters | Soft, acidic water is required. pH: 5.5-7.0, dH: up to 8 degrees. |
| Temperature | 24-27 deg C (75-81 deg F) |
| Compatibility | Softwater community |
| Lighting | Dim-Medium |
Description
The Blue Emperor Tetra is known from sluggish tributaries of the Aripuanã River, which forms part of the upper Madeira river basin in Mato Grosso, north-western Brazil. Here the waters are clear but tea coloured - a result of the tannins being released from decaying leaves that have fallen from the forest canopy above, rendering the conditions soft and acidic. The aquarium that houses Blue Emperor Tetras should be furnished with plenty of driftwood to create lots of shady areas, and the tannins that are gradually released from the wood should help to acidify the water whilst giving it a natural, clear tea-colour. Peat filtration can also help in this respect. Although plants are not found in abundance in the natural waters of this species, a moderate amount of planting will be appreciated and will help to make the fish feel more secure. Lighting should not be too bright (tannins and floating plants can help to diffuse brighter lighting), and darker substrate and background choices will help to show off their delightful colours. Unfortunately, Blue Emperor Tetras do have a rather underserved reputation for fin-nipping. This type of behaviour only really manifests when they are not maintained in sufficient numbers and when there are not enough visual barriers amongst the décor. This species should always be maintained in good sized groups of around 10 or more specimens. Not only will the fish feel more secure, but it will result in far less hostility between the males, plus it will create a much more effective and natural-looking display. Tankmates should be small and peaceful, and could include Corydoras catfish, small dwarf cichlids such as Apistogramma or Mikrogeophagus, pencilfish, and some of the smaller Loricariidae (suckermouth catfish). Avoid large, boisterous tankmates as these tetras are easily intimidated. Much attention must be paid to water quality since Blue Emperors can be sensitive to elevated nitrates and swings in water chemistry. May also be seen on sale as the Purple Emperor Tetra or the Royal Tetra. Another similar-looking fish, although from a different genus altogether, is the Emperor Tetra (Nematobrycon palmeri). Nematobrycon grow slightly larger than Inpaichthys and do not possess an adipose fin.