The Theraps irregularis, commonly known as the Irregular Cichlid, is a unique and lesser-seen Central American species admired for its natural coloration, active behavior, and riverine origins. Native to Guatemala and southern Mexico, this cichlid inhabits flowing rivers and streams where it forages along rocky and sandy substrates.
Unlike many larger, more aggressive cichlids, Theraps irregularis offers a balance of activity, personality, and more manageable temperament, making it a great choice for hobbyists looking for something different and closer to a natural biotope species.
📛 Common Name: Irregular Cichlid
🔬 Scientific Name: Theraps irregularis
🌍 Origin: Central America (Guatemala, Southern Mexico)
📏 Adult Size: 8–10 inches
😈 Temperament: Semi-aggressive / territorial
🍽️ Diet: Omnivorous (algae grazer tendencies)
🧠 Difficulty Level: Moderate
💎 Availability: Rare in the hobby
🎨 Coloration: Silver to olive body with subtle tones
🟤 Pattern: Irregular blotches and faint vertical barring
✨ Finish: Natural, slightly metallic sheen
💪 Body Type: Streamlined and built for flowing water
This species has a more natural, understated look, making it ideal for aquarists who appreciate authentic riverine fish over bright hybrids.
⚠️ Territorial, especially during breeding
🌊 Active swimmer, adapted to current
⬇️ Bottom to mid-level dwelling behavior
✔️ Can be kept with similarly sized, semi-aggressive fish
❌ May become aggressive toward smaller tankmates
Best kept:
📦 Minimum Tank Size: 75–100+ gallons
🏖️ Substrate: Sand or fine gravel
🪨 Décor: Rocks, driftwood, river-style layout
🌊 Water Flow: Moderate to strong (important)
🌿 Aquascape Tip: Replicate river habitats with current and open space
🌡️ Temperature: 72–80°F (22–27°C)
⚗️ pH: 6.5–7.8
💧 Hardness: Moderate
🌊 Water Type: Clean, well-oxygenated
🔄 Maintenance: Regular water changes recommended
🌿 Natural Feeding: Algae and biofilm grazing
🍤 Protein Foods: Pellets, insects, small invertebrates
🥬 Vegetable Matter: Spirulina, algae wafers, greens
🪱 Live/Frozen: Bloodworms, brine shrimp
A balanced diet helps maintain health and natural behavior.
| Feature | Details |
|---|---|
| 🌍 Origin | Central America |
| 📏 Max Size | 8–10 inches |
| 😈 Temperament | Semi-aggressive, territorial |
| 📦 Tank Size | 75–100+ gallons |
| ⚗️ pH Range | 6.5–7.8 |
| 🌡️ Temperature | 72–80°F |
| 🍽️ Diet | Omnivorous – algae, pellets, protein |
| 🎯 Ideal For | River-style tanks, Central American setups |
🌿 Natural Beauty: Subtle, authentic coloration
🌊 River Species: Thrives in flowing water setups
🧬 Unique Choice: Rare and uncommon in the hobby
🎯 Balanced Temperament: Less aggressive than many cichlids
The Theraps irregularis (Irregular Cichlid) is perfect for aquarists looking for a rare, active, and naturally beautiful Central American species that fits well in river-style aquariums.