Serrasalmus Pacu

Pacu are moderately aggressive and can coexist with large, non-aggressive fish. Avoid small fish that can be nipped or eaten. Provide ample space to reduce territorial disputes. Observe interactions during feeding times. Use visual barriers to reduce aggression in mixed species tanks. Separate overly aggressive individuals if necessary. Feed all species adequately to prevent food competition. Avoid housing with highly aggressive carnivores. Maintain stable water quality to reduce stress. Provide enrichment such as plants and hiding areas to promote natural behavior.

Pacu need very spacious freshwater aquariums with plenty of open swimming room and stable water conditions. Keep temperatures between 22–28 °C and maintain a pH of 6.5–7.8. Water hardness should stay within GH 4–12 and KH 3–10, closely matching their natural environment.

Use driftwood and sturdy plants to create hiding spots while leaving wide open areas for free swimming and exercise. Pacu are generally peaceful but can become stressed or competitive in cramped conditions, so avoid overcrowding and observe social interactions closely.

Provide enough space during feeding to reduce competition, and offer a balanced, nutritious diet to support healthy growth, coloration, and long-term well-being. Strong filtration and regular water changes are essential, as Pacu grow large and produce a significant bioload.

Pacu are omnivores that eat both plant and animal matter. Feed high-quality omnivore pellets as the staple diet. Supplement with fruits and vegetables such as peas, cucumbers, and melon. Offer occasional live or frozen foods to satisfy protein needs. Feed 2-3 times daily in moderate amounts. Observe feeding to ensure all fish get proper nutrition. Avoid overfeeding to prevent water quality issues. Provide dietary variety to maintain health and vitality. Remove uneaten food to prevent decomposition and algae. Monitor diet for growth and adjust as necessary.

Pacu breeding in captivity is rare but possible in large aquariums. Spawning occurs in shallow areas with submerged structures. Females lay eggs that are externally fertilized by males. Provide nutrient-rich diet to promote reproductive health. Monitor water quality closely during breeding periods. Separate eggs or fry from adults to prevent predation. Feed juveniles small, soft foods initially. Gradually introduce larger foods as they grow. Observe growth rates and adjust tank conditions accordingly. Maintain space for adult fish to reduce stress during spawning.