Fish care
Swordtail: Complete Care Guide
Last updated: May 2026
Structured care sheet for Swordtail (Xiphophorus hellerii). Validate every purchase with the free aquarium stocking calculator, parameter testing habits, and the species database table.
- Cross-check length and temperature against the species explorer.
- Track nitrate drift weekly once the tank has cycled.
- Refer to the species hub for long-form tank mate essays.
Swim room and aggression
Male swordtails spar over hierarchy; crowded foot prints amplify chasing. Long tanks beat cubes because tail extensions need turning radius—especially on high-line domestics.
Mineral-rich stability
They favour harder, alkaline water typical of livebearer setups. Soft-water pivots without remineralisation can dull colour and weaken immunity—match change water to the tank, not social media chemistry threads.
See tank mate combinations tuned to temperament overlap.
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