Quick Stats
| Adult Size | 6–8 cm |
| Minimum Tank | 5 gal |
| Temperature | 26–28°C |
| pH Range | 6.5–7.5 |
| Hardness (GH) | 4–15 dGH |
| Difficulty | Medium |
| Temperament | Semi-aggressive |
| Diet | Carnivore — betta pellets, frozen bloodworm, daphnia |
| Schooling | Keep alone (one male per tank) |
Tank Setup
The Koi Betta (Betta splendens (koi)) requires a minimum tank size of 5 gal. For a species this size, a larger tank is always better — more water volume means more stable parameters and a healthier environment.
Water parameters should be maintained within the following ranges: temperature 26–28°C, pH 6.5–7.5, and hardness 4–15 dGH. These fish are sensitive to water quality — test regularly and maintain pristine conditions.
Provide appropriate hiding places, a suitable substrate, and planted areas to match the natural behaviour of this species.
Tank Mates
Koi Betta are semi-aggressive fish. Choose tankmates carefully — they may not be suitable for all community setups.
Compatible tank mates include: Pygmy Corydoras, Nerite Snail, Mystery Snail, Otocinclus (cautiously). Always ensure all species share similar water parameter requirements before mixing.
Schooling requirements: Keep alone (one male per tank).
Diet & Feeding
Koi Betta are Carnivore. Their diet should reflect their natural feeding habits.
Carnivore — betta pellets, frozen bloodworm, daphnia
Feed small amounts 1–2 times daily. Only provide what the fish can consume within 2–3 minutes to prevent overfeeding and water quality issues. Supplement with live or frozen foods for optimal health and colour.
Common Health Issues
Like all aquarium fish, Koi Betta can be susceptible to common diseases including ich (white spot disease), fin rot, and bacterial infections. This species can be sensitive — maintain excellent water quality to prevent health issues.
Prevention is always better than treatment. Maintain stable water parameters, avoid overfeeding, quarantine new fish before adding them to the main tank, and perform regular water changes. Test your water weekly and address any parameter spikes immediately.
If disease does occur, isolate affected fish in a quarantine tank and treat appropriately. Always research medication compatibility before use — some treatments are toxic to invertebrates and scaleless fish.
Breeding
Breeding Koi Betta requires specific conditions and may be challenging for beginners.
Provide appropriate breeding conditions — caves or hiding places for egg-laying species. Condition breeding pairs with high-quality foods before attempting to spawn them.
Research specific breeding requirements for this species before attempting it.
Frequently Asked Questions
What size tank does a Koi Betta need?
A Koi Betta needs a minimum tank size of 5 gal. However, larger is always better — more water volume means more stable water parameters and healthier fish.
Are Koi Betta easy to keep?
Koi Betta are rated as Medium difficulty. Some experience with aquarium water parameters is recommended before keeping this species.
What do Koi Betta eat?
Koi Betta are Carnivore. Feed a varied diet including betta pellets, frozen bloodworm, daphnia.
Can Koi Betta live with other fish?
Koi Betta are semi-aggressive. Compatible tankmates include: Pygmy Corydoras, Nerite Snail, Mystery Snail, Otocinclus (cautiously). Always research compatibility before mixing species.