Bonti sailfin silverside

Telmatherina bonti

Also known as Bonti rainbowfish

FreshwaterFish

Bonti sailfin silverside (Telmatherina bonti) — The Wet Spot Tropical Fish · Used with permission

Care at a glance

Temperature: 77–84°F (25–29°C)
pH: 7.2–8.5
Adult size: 3 in (7.5 cm)
Minimum tank: 24 gal (90 L)
Temperament: Peaceful
Social behavior: Schooling
Swim level: Middle
Difficulty: Medium
Breeding: Medium
Rarity: Rare
Origin: Malili Lakes region, Sulawesi, Indonesia
Family: Telmatherinidae

Overview

Keep this lively silverside as a school of eight or more in hard, warm, alkaline water, since fish from its ancient lakes do poorly in soft, acidic conditions. It is peaceful and active in the middle water, and a group brings out the males, which raise their pennant fins and display almost constantly. Give it open swimming room with some plants and a tight cover, as it is a keen jumper. Fine live and frozen foods keep it in colour and condition: daphnia, cyclops, brine shrimp, and small frozen items, alongside a good flake. A tank of about 90 litres or more suits a group.

In the wild

It is native to the Malili lakes system of Sulawesi in Indonesia, a set of ancient, hard, alkaline lakes and their connecting streams, shared with the region's well-known shrimp and snails. Match that water closely: warm, 25 to 29 degrees Celsius, and distinctly alkaline at pH 7.2 to 8.5, with open water, some rock and plants, and a stable, well-filtered set-up.

Good to know

It belongs to the sailfin silverside family, Telmatherinidae, the Sulawesi cousins of the Celebes rainbowfish, and reaches about 7.5 cm. Males carry extended pennant-like fins used in display. The species is a continuous spawner that scatters small numbers of eggs among fine plants over time, of moderate breeding difficulty.

Did you know

It comes in more than one colour at once. Within a single wild population, yellow, whitish, and yellow-and-white individuals mix and breed together freely, and biologists still do not know what the colour differences are for.

Tank mates

Bonti sailfin silverside is a peaceful, schooling species that keeps to the middle. These picks match on water type, temperature, pH, size and temperament.