Easy
Swordtail Black (Xiphophorus helleri black)
23–27°C · pH 7–8.5 · 90L
£3.99
Montezumae Swordtail — petite 4 cm Mexican line for hard, alkaline water. Peaceful, easy care, suitable for tanks from just 60 litres.
Adult size is the maximum length this species reaches at full maturity (scientific sources). The livestock you receive will be younger and smaller — pick a size variant above for the actual shipping size. Photos are AI-enhanced, so the animal may show subtle colour or marking differences.
Xiphophorus helleri montezumae
Swordtail Montezumae are a shoaling species — they need 6+ to feel safe and show their full colour. Larger shoals stay calmer, eat better, and look stunning.
Montezumae Swordtail — petite 4 cm Mexican line for hard, alkaline water. Peaceful, easy care, suitable for tanks from just 60 litres.
Adult size is the maximum length this species reaches at full maturity (scientific sources). The livestock you receive will be younger and smaller — pick a size variant above for the actual shipping size. Photos are AI-enhanced, so the animal may show subtle colour or marking differences.
Platies are one of the best beginner fish — hardy, colourful, peaceful, and available in dozens of colour varieties. Perfect for community tanks of all sizes.
Maintain these water conditions for optimal health and vibrant colors
Hard, alkaline water is where this Mexican line feels most at home, which makes the Montezumae Swordtail (Xiphophorus helleri montezumae) a thoroughly practical choice for keepers whose water leans that way. If your kettle furs up quickly, your supply is probably exactly what this fish enjoys. It is petite — listed at 4 cm — and with a listed minimum tank of just 60 litres it opens swordtail keeping to more modest aquariums than the family usually demands. Most swordtails ask for three-figure tank volumes; this line's 60-litre listing is the exception that makes it worth a second look.
True to its relatives, it is peaceful and easy to care for. Suitable companions include other peaceful livebearers, platies, mollies, guppies, peaceful tetras and Corydoras catfish; large aggressive cichlids, fin-nipping barbs, aggressive or highly territorial species, large predators and very delicate slow-moving fish are the ones to refuse. The companion options span a small community comfortably, so even a compact aquarium can feel fully stocked without breaking the peace.
Water parameters mirror its hard-water leanings: pH 7.0–8.5, hardness from 5 to 30 dGH and a temperature of 23–27 °C. Despite the smaller tank allowance, the usual rules still apply — stable temperature, clean filtered water and a varied menu for an omnivorous feeder. It swims at the middle level and typically lives about three years.
Sixty litres is an achievable footprint for most homes, making this a swordtail you can plan around rather than upsize for. For a desk-side or bedroom aquarium, few swordtails fit the brief as neatly. Combine it with gentle community species and hard-water-tolerant planting for a coherent set-up. Acclimatise with patience and it settles into the middle of the tank, exactly where the care sheet says it lives. Your order is handled by a licensed live-animal courier and protected by our live arrival guarantee.
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