TankBud

Redtail splitfin

Xenotoca eiseni

Also known as Redtail goodeid, Orangetail goodeid, Red tail goodeid

FreshwaterFish

Redtail splitfin (Xenotoca eiseni)
Auteur: Marie France Janelle Original uploader was Mariejanelle at fr.wikipedia · CC BY-SA 2.5

Care at a glance

Temperature
64–82°F
18–28°C
pH
7.0–8.0
Adult size
2.8 in
7 cm
Minimum tank
20 gal
75 L
Temperament
Mostly peaceful
Social behavior
Social
Tankmates
With caution
Swim level
Middle
Difficulty
Easy
Breeding
Livebearer · Easy
Rarity
Rare
Family
Goodeidae
Origin
Native to the Rio Grande de Santiago drainage and waters near Compostela, Nayarit, in west central Mexico, in springs, pools, and slow streams.

Overview

The redtail splitfin is a stocky, hardy goodeid for a roomy group tank with hard water. It is easy to keep.

Did you know

The red band on a dominant male's tail can flush brighter or fade within minutes, depending on his mood and status in the group.

Caring for the redtail splitfin

Keep six or more redtail splitfins in a roomy tank of 20 gal (75 L) or larger. Give them some plant cover plus open water to cruise, with steady filtration.

Keep the water medium hard to hard and alkaline, at 64 to 82°F (18 to 28°C) and a pH of 7.0 to 8.0. They tolerate that whole range. Feed a varied diet with plenty of vegetable matter, since they graze algae.

Redtail splitfins are notorious fin nippers. Keep them away from guppies, angelfish and other slow, long-finned fish. A decent-sized group helps spread out the nipping.

Males are a little smaller than females, at about 6 cm. Dominant males show a brilliant orange to red band across the rear body, with a blue-green sheen ahead of it. The redtail splitfin is a livebearer and easy to breed, with broods of 10 to 40 large fry.

Good to know

The redtail splitfin complex was revised in 2016. The bright San Marcos form was split off as a separate species, Xenotoca doadrioi, and other populations went to Xenotoca lyonsi. That left true X. eiseni for the Santiago basin fish. Like all goodeids, the females feed their developing embryos internally through trophotaeniae.

In the wild

The redtail splitfin is native to the Rio Grande de Santiago drainage and waters near Compostela, Nayarit, in west central Mexico. It lives in springs, pools and slow streams.

Common questions

What size tank does a redtail splitfin need?

A redtail splitfin needs at least 20 gal (75 L). It spends most of its time in the middle.

What temperature and pH does a redtail splitfin need?

A redtail splitfin is comfortable at 64–82°F (18–28°C) with a pH of 7.0–8.0.

What does a redtail splitfin eat?

A redtail splitfin eats a varied diet with plenty of vegetable matter. It also grazes algae.

How big does a redtail splitfin get?

An adult redtail splitfin reaches about 2.8 in (7 cm).

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

Males are a little smaller than females, at about 6 cm. Dominant males show a brilliant orange to red band across the rear body, with a blue-green sheen ahead of it.

How does a redtail splitfin breed?

Redtail splitfins are livebearers and easy to breed. Broods run from 10 to 40 large fry.

Related species