Betta simplex – Peaceful Mouthbrooding Wild Betta

Betta simplex is a rare and peaceful wild betta species native to southern Thailand, admired for its natural coloration, calm temperament, and fascinating paternal mouthbrooding behavior.

Species Overview

• Scientific Name: Betta simplex

• Common Name: Simplex Betta

• Origin: Krabi Province, Thailand

• Type: Wild Betta (Paternal Mouthbrooder)

• Temperament: Peaceful compared to most bettas

Unlike ornamental Betta splendens, Betta simplex is known for its relatively calm personality and ability to live in small groups under proper conditions.

Appearance & Characteristics

• Slender elongated body typical of wild bettas

• Soft brown, beige, or olive coloration

• Iridescent blue or turquoise highlights on fins and body

• Rounded fins with subtle patterning

• Males develop stronger coloration during courtship

• Large mouth adapted for paternal mouthbrooding

While less flashy than ornamental bettas, their natural elegance and behavior make them highly attractive to wild betta enthusiasts.

Size & Lifespan

• Adult Size: 6–7 cm

• Lifespan: 4–5 years with proper care

• Mature coloration develops gradually as fish age

Ideal Water Conditions

Betta simplex comes from limestone karst regions and prefers slightly alkaline water compared to many wild bettas.

• Temperature: 24–28°C

• pH: 7.0–8.0

• Hardness: 5–15 dGH

• Filtration: Gentle sponge or low-flow filter

• Water Flow: Mild

• Water Changes: 20–30% weekly

Stable water parameters are important to keep this species healthy and stress-free.

Recommended Aquarium Setup

• Minimum Tank Size: 40 liters for a pair or small group

• Sand or fine gravel substrate

• Natural décor such as rocks and driftwood

• Moderate lighting

• Live plants such as:

  • Java fern

  • Anubias

  • Cryptocoryne

• Plenty of hiding places and caves

• Secure lid required (bettas are jumpers)

A calm environment encourages natural behavior and breeding activity.

Tank Mates Compatibility

This species is more tolerant than many bettas and may live peacefully with:

• Small rasboras

• Peaceful tetras

• Corydoras catfish

• Small loaches

Avoid:

• Aggressive fish

• Fin-nipping species

• Large territorial fish

Many aquarists keep them in species-only tanks to observe natural behavior.

Feeding Habit

Betta simplex is carnivorous and prefers small protein-rich foods.

Suitable foods include:

• Live or frozen bloodworms

• Brine shrimp

• Daphnia

• Mosquito larvae

• High-quality micro pellets

Feeding tips:

• Feed 1–2 small meals daily

• Offer varied diet for best health

• Remove uneaten food to maintain water quality

Breeding Behavior

• Paternal mouthbrooder

• Male incubates eggs in mouth for about 9–14 days

• Fry are relatively large when released

• Fry can accept baby brine shrimp immediately

Breeding is easier compared to many other wild bettas.

Why Choose Betta simplex?

• Rare wild betta species from Thailand

• Peaceful temperament compared to most bettas

• Fascinating paternal mouthbrooding behavior

• Suitable for species tanks or calm communities

• Excellent for wild betta collectors

Betta simplex is an outstanding choice for aquarists who enjoy observing natural fish behavior and maintaining unique wild betta species in a carefully designed aquarium.