Australian Sea Apple

The Australian Sea Apple (commonly Pseudocolochirus species) is a filter-feeding sea cucumber found in Indo-Pacific reef environments, typically anchored in areas with steady water movement. Unlike cleanup crew scavengers, sea apples rely entirely on suspended food in the water column, using their feather-like feeding tentacles to capture phytoplankton and organic particles.

They are stationary for most of their lives, attaching to rockwork where they can extend their feeding arms into consistent flow. Their bright coloration serves as a warning in the wild, as they can release toxins when severely stressed.

Care Requirements

Care Level: Advanced – Requires stable parameters and consistent feeding
Minimum Tank Size: 50+ gallons
Aquarium Setup: Established reef tank with moderate to strong, indirect flow

Australian Sea Apples need a mature system with a constant supply of suspended nutrients. They should be placed in an area where flow brings food directly to them without blasting their body.

Diet & Nutrition

Australian Sea Apples are obligate filter feeders and depend entirely on fine particulate foods in the water column.

Diet: Filter Feeder – Requires constant access to suspended food
Recommended Foods:

• Live phytoplankton (preferred and most effective)
• Rotifers and other microplankton
• Powdered coral foods and fine particulate blends

Target feeding or broadcast feeding multiple times per week is often necessary. Tanks that are too “clean” can lead to starvation over time.

Lifespan & Growth Rate

Lifespan: 5–10 years (with proper care)
Growth Rate: Slow

Given stable conditions and consistent feeding, they can live for several years, though long-term success in captivity is less common due to feeding challenges.

Temperament & Compatibility

Temperament: Peaceful – Non-aggressive and stationary
Reef Safe? Yes (with caution)

They do not bother corals or fish. However, they should not be kept with fish or invertebrates that may nip at them, as stress can lead to toxin release.

Common Challenges & Considerations

Toxin Release Risk:
If stressed, injured, or dying, sea apples can release toxins that may harm or wipe out tank inhabitants.

Feeding Difficulty:
Requires consistent availability of suspended foods. Many tanks do not naturally produce enough nutrition to sustain them.

Flow Placement:
Too little flow leads to starvation, while too much direct flow can cause them to detach or become stressed.

Intake Hazards:
Can be injured by powerheads or overflows. Use guards on pumps and intakes.

Water Conditions

Temperature: 75–77°F
dKH (Alkalinity): 8–9
pH: 8.1–8.3
Specific Gravity: 1.024–1.026

Stable, well-oxygenated water with consistent nutrient availability is critical for long-term success.