Can Ocellaris Clownfish live with Siamese Algae Eater?
High risk due to water mismatch, aggression, or predation.
Why Ocellaris Clownfish and Siamese Algae Eater Don't Make an Easy Pair
The size gap is 3.0" — Ocellaris Clownfish (3.0") and Siamese Algae Eater (6.0"). A fish that fits in another fish's mouth will eventually end up there.
Ocellaris Clownfish
Amphiprion ocellaris
| Adult Size: | 3.0" |
| Temperament: | semi-aggressive |
| Min Tank: | 20 gal |
| Temperature: | 74-80°F |
| pH Range: | 8.1-8.4 |
Siamese Algae Eater
Crossocheilus oblongus
| Adult Size: | 6.0" |
| Temperament: | peaceful |
| Min Tank: | 30 gal |
| Temperature: | 75-82°F |
| pH Range: | 6.5-7.5 |
Water Parameter Overlap
| Parameter | Ocellaris Clownfish | Siamese Algae Eater | Overlap |
|---|---|---|---|
| Temperature | 74-80°F | 75-82°F | 5°F ✓ |
| pH | 8.1-8.4 | 6.5-7.5 | No overlap ✗ |
Compatibility Breakdown
Temperament Match: semi-aggressive + peaceful. Semi-aggressive → watch territory and feeding.
⚠️ Size Predation Risk: Ocellaris Clownfish (3.0") vs Siamese Algae Eater (6.0"). A 3.0" gap — the larger fish will view the smaller fish as food.
Score: 40/100 (GOOD ≥80, CAUTION ≥50, RISKY <50).
🔧 Tank Setup Requirements (for Both)
- Minimum tank: 30 gallons — sized for the larger fish in the pair.
- Temperature: keep it between 75°F and 80°F.
- pH: no shared range. One species will be outside its tolerance regardless of what you set.
- Hiding spots: essential for Ocellaris Clownfish — caves, plants, or driftwood to retreat when feeling stressed.
- Water changes: 25% weekly minimum. Two species mean double the bioload.
🔧 Tank Stocking Calculator
Enter tank size to calculate safe stocking levels:
Recommended Equipment
Based on tank size 30+ gallons:
Herbivore sinking rounds for algae eaters
Explore Related Checks
See what else works with these fish:
⚠️ Common Reasons This Pairing Fails in Practice
- Size-based predation: The 3.0" size gap means the larger fish may eat the smaller one once it grows to full size. This is not fixable with more hiding spots.
- Overcrowding: Even compatible species fail in tanks that are too small. Double the species means double the bioload — 25% weekly water changes are the minimum.
- Inadequate acclimation: Adding both species on the same day without quarantine is a common mistake. Always drip-acclimate new arrivals and quarantine for 2–4 weeks.
- Mismatched feeding: Ocellaris Clownfish is a omnivore while Siamese Algae Eater is a herbivore. Use targeted feeding zones and sinking vs. floating food to ensure both get proper nutrition.
Tools & Resources
Accuracy note: This tool uses expert rules + FishBase.org data. Individual fish behavior varies — a semi-aggressive individual Ocellaris Clownfish may act differently from its species average. Always observe, quarantine new arrivals for 2-4 weeks, and avoid overcrowding. If a pairing says CAUTION, start with a smaller group and a lid.