TankBud

Relict splitfin

Xenoophorus captivus

Also known as Relict goodeid

FreshwaterFish

Relict splitfin (Xenoophorus captivus)
Cedricguppy - Loury Cédric · CC BY-SA 4.0

Care at a glance

Temperature
61–79°F
16–26°C
pH
7.0–7.8
Adult size
2.4 in
6 cm
Minimum tank
16 gal
60 L
Temperament
Peaceful
Social behavior
Social
Tankmates
With caution
Swim level
Middle
Diet
Omnivore
Difficulty
Medium
Breeding
Livebearer · Medium
Rarity
Very rare
Family
Goodeidae
Origin
Endemic to the upper Rio Verde headwaters in San Luis Potosi, Mexico, in springs and small creeks with hard water.

Overview

The relict splitfin is a small, peaceful goodeid for a cool, planted species tank. It is a step up from the easiest fish.

Did you know

The relict splitfin survives in only a handful of highland spring systems. Most aquarium fish trace back to a few carefully bred lines.

Caring for the relict splitfin

Keep a group of six or more relict splitfins in 16 gal (60 L) or larger. A planted tank with clean, gentle flow suits them.

This subtropical fish neither needs nor wants tropical heat. Keep the water medium hard to hard, at 61 to 79°F (16 to 26°C) and a pH of 7.0 to 7.8. Cooler room temperatures suit it better than a warm community tank.

Base the diet on vegetable foods and algae, such as spirulina flake and blanched greens, with a little frozen daphnia. Relict splitfins are avid algae grazers. They are peaceful and best in a species tank or with other calm, cool-water goodeids.

Males show a spangled blue-green body with a yellow or orange tinge in the fins. The relict splitfin is a livebearer, and females give birth to broods of roughly 10 to 25 fry after about 55 days. Breeding is of medium difficulty.

Good to know

The relict splitfin, Xenoophorus captivus, is the only species in its genus. It is critically endangered as its springs are drained and polluted. The mother feeds her developing young internally through trophotaeniae.

In the wild

The relict splitfin is endemic to the upper Rio Verde headwaters in San Luis Potosi, Mexico. It lives in cool highland springs and small creeks with hard water.

Common questions

What size tank does a relict splitfin need?

A relict splitfin needs at least 16 gal (60 L). It spends most of its time in the middle.

What temperature and pH does a relict splitfin need?

A relict splitfin is comfortable at 61–79°F (16–26°C) with a pH of 7.0–7.8.

What does a relict splitfin eat?

A relict splitfin eats a diet based on vegetable foods and algae, such as spirulina flake and blanched greens. Add a little frozen daphnia.

How big does a relict splitfin get?

An adult relict splitfin reaches about 2.4 in (6 cm).

How can you tell a male relict splitfin from a female?

Males show a spangled blue-green body with a yellow or orange tinge in the fins.

How does a relict splitfin breed?

Relict splitfins are livebearers. A female gives birth to roughly 10 to 25 fry after about 55 days, and breeding is of medium difficulty.

Related species