AquaMateCheck Fish Compatibility & Tank Mate Checker

Can Angelfish live with Oscar?

🟡 CAUTION

Case-by-case. Watch group sizes, tank size, and feeding zones.

Angelfish

Pterophyllum scalare

Adult Size:5.9"
Temperament:semi-aggressive
Min Tank:40 gal
Temperature:75-82°F
pH Range:6.5-7.5
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Oscar

Astronotus ocellatus

Adult Size:12.0"
Temperament:aggressive
Min Tank:75 gal
Temperature:74-81°F
pH Range:6.0-7.5
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Water Parameter Overlap

Parameter Angelfish Oscar Overlap
Temperature 75-82°F 74-81°F 6°F ✓
pH 6.5-7.5 6.0-7.5 1.0 ✓

Why CAUTION?

Temperament Match: semi-aggressive + aggressive. One aggressive → predation/nipping risk.

⚠️ Size Predation Risk: Angelfish (5.9") vs Oscar (12.0"). Large size difference → larger fish may eat smaller fish.

Score: 55.0/100 (CAUTION threshold: GOOD ≥80, CAUTION ≥50, RISKY <50).

🔧 Tank Stocking Calculator

Enter tank size to calculate safe stocking levels:

Recommended Equipment

Based on tank size 40+ gallons:

Fluval Flex Aquarium Kit — $149.99

57-gallon kit suitable for angelfish

Accuracy note: This tool uses expert rules + FishBase.org data. Individual fish behavior varies. Always observe, quarantine new arrivals for 2-4 weeks, and avoid overcrowding.