
Source: Wikimedia Commons
Xenotoca eiseni
A livebearer whose caudal peduncle turns orange to red. A Mexican goodeid, it is extremely hardy, but it sometimes attacks the fins and eyes of other fish, so a species tank is the safer choice.
Xenotoca eiseni is a Mexican goodeid livebearer. FishBase gives a total length of 6.0cm for males and 7.0cm for females. The caudal peduncle colours orange to red, and mature males develop a raised back. It occupies habitats from clear mountain streams to polluted roadside ditches, and Seriously Fish gives 15-30C, pH 6.0-8.0, 10-20dGH and a 60 x 30cm tank of about 54 litres. Its temperament is unpredictable. Some individuals settle into a community while others nip fins or attack and kill other species, and Seriously Fish notes that it is especially bad with catfish, citing cases of stripped fins and eaten eyes in Corydoras, and recommends a species tank. Breeding is easy, and goodeids differ from other livebearers in nourishing the embryos through a structure called the trophotaenia. Gestation lasts seven to eight weeks and produces five to fifty large, well-developed young. The IUCN assessed it as Endangered in 2018.
Source: Wikipedia (CC BY-SA 4.0)
The Redtail Splitfin lives 3-5 years.
The Redtail Splitfin grows to 6-7cm.
The ideal temperature for the Redtail Splitfin is 15〜30℃.
Origin
Central America (Mexico)
Lifespan
3-5 years
Sources: FishBase / Seriously Fish / FishBase (Xenotoca doadrioi)
Edited & verified by: BreederDirect editorial team
The taxonomic, regulatory, and husbandry data on this page are compiled and verified against the authoritative primary sources below.
Accepted name: Xenotoca eiseni (Rutter, 1896)
Authority databases: FishBase
Nomenclature follows global taxonomic authority databases.
Sources: CITES Appendices (species not listed) / IUCN Red List
Regulations may change. Always verify the latest information with the relevant authorities.
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Size
6-7cm
Temperature
15〜30℃
Prepared foods, frozen foods, live foods
Seriously Fish suggests a 60 x 30cm base of about 54 litres. Dense planting over a dark substrate shows the colour to best effect.
Seriously Fish gives 15-30C, pH 6.0-8.0 and 10-20dGH. FishBase records a wide 15-32C in the wild, reflecting its adaptability.
Seriously Fish calls its behaviour unpredictable and recommends a species tank. It may nip fins or kill other species, and combinations with catfish such as corydoras should be avoided.
Unfussy, it accepts dried, frozen and live foods alike.
Breeding is easy. Females cannot store sperm, so each brood requires a fresh mating. Gestation is seven to eight weeks and produces five to fifty young. Newborns may carry what looks like an umbilical cord; this is normal and disappears in two or three days.
Seriously Fish describes it as incredibly hardy and adaptable. IUCN status is Endangered. Stock labelled San Marcos may belong to the separate species Xenotoca doadrioi, so check the locality given.
Beginner. This is a beginner-friendly species. No special equipment or experience is required, and it can be kept successfully with basic care setup.
The ideal temperature for Redtail Splitfin is 15〜30℃. Avoid sudden temperature changes and maintain a stable environment.
The average lifespan of Redtail Splitfin is 3-5 years. With proper care and nutrition, they can live a long and healthy life.
Redtail Splitfin typically reaches 6-7cm as an adult. Size may vary depending on care conditions and individual genetics.
Redtail Splitfin feeds on: Prepared foods, frozen foods, live foods. Aim for a balanced diet with appropriate feeding frequency.
The price of Redtail Splitfin varies significantly depending on morph, size, and lineage. Check our market price page for the latest pricing information.
Last updated: September 17, 2026