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Panuco Swordtail

Xiphophorus nigrensis

Freshwater Central America Usually captive bred

A natural, slender swordtail from northeastern Mexico known for producing distinct small and large male morphs. It is exceptionally lively and thrives in clean, hard, slightly alkaline conditions. Provide a spacious tank with decent water flow and a secure lid to prevent sudden escapes.

5.5 cm adult length, drawn to scale. torpedo body.

Try it in the planner Opens a tank sized to its minimum with 5 fish added.

What it needs

ItemValueBecause
Adult length 5.5 cm Used for the Space check: the tank must be long enough for the fish to turn round.
Smallest tank 70 L, at least 60 cm long estimated The least water and floor length this species is kept in for good, as a single fish or smallest group.
Extra water per added fish 10 L estimated What each further fish adds once the minimum is met.
Waste load Class 2 of 5 estimated How much waste an adult makes against its size. Feeds the Load check.
Temperature 21 to 26 C Stock sharing a tank need overlapping ranges.
pH 7.2 to 8.2 Compared with tankmates in the Water check.
Hardness GH 10 to 25, KH 5 to 15 Degrees of general and carbonate hardness.
Flow Medium Low-flow fish are stressed in a strong current.
Light Moderate Matched to the lighting class on the needs sheet.
Group size At least 5, ideally 8 Kept alone or in small numbers it hides, fades or turns on tankmates.
Temperament Peaceful Territorial: weak.
Swims in All levels Fish that use different levels share a tank more easily.
Lifespan About 4 years A fish is a long commitment.
Experience Suits a first tank A guide to how forgiving the species is of mistakes.
Jumps Yes Keep the tank covered.

Tags marked estimated are judged from the size and habits of the species rather than measured, so treat them as a sensible default.

Diet and tank layout

Panuco Swordtail is an omnivore that swims in all levels of the tank. It is safe with plants. Give it some cover.

Tankmates

Works with

No close matches in the data. Check the pair tool.

Depends

Avoid

Compare any two fish on the compatibility page, or print the equipment for a stock on the needs sheet. How this is worked out: the method.