Altum Angelfish (Pterophyllum altum)
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Fish Focus for you today! 
The Pterophyllum altum more commonly known as the Altum Angel, Deep Angel or Orinoco Angel, first described and named by the French zoologist Jacques Pellegrin in 1903.
The altum is the largest of the angels and can reach over 35cm in height from tip of dorsal fin to tip of anal fin. Like its better known cousin, the Pterophyllum scalare, altums are silver in colour with 3 horizontal bars brownish/red in colour, the fins can also show red striations and adults may have red spots and exhibit a bluish/green dorsal overcast. What really distinguishes the altum from the other angels is the notch on its forehead just above the eye-socket, they are the only angels to exhibit this feature.
Altums are native to Columbia and Venezuela where they are found in the well oxygenated upper Rio Negro and tributaries of the upper Rio Orinoco, where they thrive in the warm, extremely soft water (28-32°C, pH 4.5-6.0, KH 0-4°H) which should be replicated as closely as possible when keeping these fish.
Due to their size, altums will need a large, tall, well filtered aquarium although they don’t like a fast flow so spray bars and diffusers should be used to dissipate the flow from the filter outlet. Altums are quite shy and skittish by nature so an aquarium densely planted with broad leaf plants and covered with floating plants along with bogwood or azalea roots to simulate fallen and overhanging branches. As they like to dig for food, a sand or very fine gravel should be used for the substrate.
Altums can be tricky feeders at first usually requiring a good supply of livefood until they are settled at which point you can start to wean them onto a good quality slow sinking, granula food. Tank mates for altums should be able to thrive in warm soft conditions making discus and some larger tetras such as cardinals ideal; but remember angels are cichlids and will make a meal of any fish small enough to fit in their mouths.
