Can Flagtail Prochilodus and Pink Tailed Chalceus Live Together?

Both Flagtail Prochilodus and Pink Tailed Chalceus are moderately assertive species with an aggression score of 6/10. Their matching temperaments mean neither fish is likely to dominate the other in a shared aquarium.

In terms of spatial distribution, Flagtail Prochilodus prefers the Middle (Open Water) and Bottom (Substrate) zones, whereas Pink Tailed Chalceus occupies the Top (Surface) zone. Because they use different levels of the water column, territorial disputes are less likely and the tank will appear more balanced.

Worth noting: Flagtail Prochilodus is a known jumper, so a tight-fitting lid is essential.

The safe temperature window for both species falls between 23°C and 28°C. Aim for the midpoint of this range (around 25.5°C) for optimal comfort.

Both fish can tolerate a pH between 6 and 7.5. Maintaining a stable value within this band is more important than hitting an exact number.

For general hardness, the shared comfort zone is 5–15 dGH. Regular testing will ensure conditions stay within this range.

To house Flagtail Prochilodus and Pink Tailed Chalceus together, plan for an aquarium of at least 500 litres with a minimum length of 150 cm. This recommendation combines the stricter species minimums with a community-load allowance so the pairing has realistic long-term space and filtration headroom.

Because this pairing requires extra vigilance, include plenty of hiding spots — caves, driftwood, and dense plant clusters — so the less dominant fish can retreat when needed.

Specific environmental needs for this combination include: Established Algae (Otocinclus), Driftwood (Digestion/Hiding), Plants - Floating. Meeting these requirements will help both species thrive.

Both species do well with high (river/stream) water movement, so a standard filtration setup rated for the tank volume should suffice.