Delta Betta

Betta splendens

Animalia›Chordata›Actinopterygii›Anabantiformes›Osphronemidae

Variety of Halfmoon Betta · Delta

📍 Southeast Asia (captive-developed)

Betta with a caudal fin that fans to a wide delta (triangle) shape, opening to about 120 degrees. A balance between the flowing veiltail and the fully fanned halfmoon — active and manageable.

Size3"

Min Tank5g

semi-aggressive

Zonetop

Care Guide

Diet

Delta bettas are carnivorous and require high-protein foods including quality betta pellets, frozen bloodworms, and frozen brine shrimp. Feed small portions once daily, only what they can consume in 2-3 minutes. Occasional live food like mosquito larvae enriches their diet and encourages natural hunting behavior.

Behavior

Delta bettas are semi-aggressive with moderate fin display and territorial tendencies, though less extreme than halfmoons. They are active swimmers that patrol the upper water column and appreciate space to flare and explore. Males are solitary and must be housed individually; females can sometimes be kept in groups (sorority) only with careful planning and ample space.

Breeding

Breeding delta bettas in captivity is moderately difficult and requires careful conditioning of both sexes, proper water parameters, and a dedicated breeding tank. Males build bubble nests and will guard fry aggressively. Fry are small and require infusoria or liquid fry food for the first week before graduating to micro pellets.

Tank Mates

Otocinclus

Peaceful bottom-dweller that won't compete for food or space; avoid fin-nipping species

good

Ramshorn Snail

Slow-moving snails are ignored by bettas and help maintain water quality

excellent

Emerald Dwarf Rasbora

Small, peaceful schooling fish that occupy mid-water; keep in groups of 6+ to reduce stress

good

Nerite Snail

Hardy algae-eaters that are too armored for bettas to harm; excellent tank cleaners

excellent

Common Diseases

Fin Rot

Symptoms

Frayed, discolored, or deteriorating fin edges; lethargy; loss of appetite

Treatment

Perform 25-50% water changes every 2-3 days, maintain pristine water quality, and treat with aquarium salt (1 tsp per gallon) or antibacterial medication if severe

Ich (Ick)

Symptoms

White spots on body and fins, scratching against objects, rapid breathing, clamped fins

Treatment

Raise temperature gradually to 28-30°C, treat with ich medication or aquarium salt, perform daily water changes, and ensure good filtration

Velvet Disease

Symptoms

Fine golden or rust-colored dust on body, lethargy, rapid gill movement, loss of appetite

Treatment

Increase temperature to 28-30°C, dim lighting to reduce stress, treat with copper-based medication or salt, and perform frequent water changes

Dropsy

Symptoms

Swollen belly, pinecone-like scales, lethargy, loss of appetite, difficulty swimming

Treatment

Isolate in hospital tank, maintain excellent water quality with frequent changes, feed high-quality foods, and treat with antibiotics if bacterial; prognosis is often poor