Swordtail tank mates
Larger livebearer with the same hard-water needs as mollies. Males push each other in cramped tanks and the species jumps.
Lists below are built from this species record (safest, best with, risky, unsafe) — each link opens a pair-level check, not a guarantee.
Best tank mates (on file)
Merged from conservative safest and best with fields — de-duplicated by species.
The Swordtail profile lists Cherry Barb as both safe and a recommended pairing. Cherry Barb schools in groups of 6 or more, so plan room for the whole group rather than one fish.
The Swordtail profile lists Corydoras Catfish as both safe and a recommended pairing. Corydoras Catfish schools in groups of 6 or more, so plan room for the whole group rather than one fish. Corydoras Catfish swims in the bottom zone while Swordtail stays in the middle, so the two will not crowd the same water column.
The Swordtail profile lists Guppy as both safe and a recommended pairing. Guppy is a peaceful beginner-care species with a 40L minimum. Run the pair checker for your specific tank before stocking.
The Swordtail profile lists Molly as both safe and a recommended pairing. Molly is a peaceful beginner-care species with a 80L minimum. Run the pair checker for your specific tank before stocking.
The Swordtail profile lists Platy as both safe and a recommended pairing. Platy is a peaceful beginner-care species with a 60L minimum. Run the pair checker for your specific tank before stocking.
Risky or situational
From risky tank mates and broad avoid with (excluding “unsafe” below). May work with species-only setups, more water, or mature systems — read the pair page.
None on file beyond the safe list.
Fish to avoid with Swordtail
From the unsafe list — predation, aggression, or space rules on this profile.
Betta conflicts with Swordtail on temperament, predation, or footprint. The juvenile size in a shop tank is not the figure that matters here.
Tiger Barb conflicts with Swordtail on temperament, predation, or footprint. The juvenile size in a shop tank is not the figure that matters here.
Oscar reaches 35cm and is flagged predatory. Swordtail at 12cm is prey-sized for it. Oscar needs at least 300L, far above the 80L minimum for Swordtail. The tank that houses one stresses the other.
Tank size and groups
- Published minimum for Swordtail: 80L — group minimum 3 .
- Compatibility changes when the tank is too short for turning, too little for a real school, or too warm for one species and not the other — that is why pair checks include tank context, not only temperament.
- Nearest litre hub to this minimum: 80L hub.
Easier alternatives to consider
Conservative beginner-peaceful picks from the library — not replacements for reading, but a shorter on-ramp than this species for a first tank.
Plan before you buy
Pair checks for every mix, then multi-species stocking in the builder.
Filtration & heating
A 80L minimum tank for Swordtail needs a filter rated for at least 320L/hr turnover and a heater maintaining 20–28°C.
Similar fish (same category)
- Molly — min 80L
- Platy — min 60L
- Endler's Livebearer — min 40L
- Guppy — min 40L
- Sailfin Molly — min 120L
Related (care + temperament)
Other species that list Swordtail
Reverse lookup: these profiles reference Swordtail under safe or “best with” lists.