🏠The Swordtail tank: 100 L, hardware and start-up
Swordtail : A tank of at least 100 L and at least 80 cm long, covered since it jumps very well. A recommended group is one male to three or more females.
In short: 8 to 12 cm as an adult including the sword, 100 L minimum, water between 22 and 26 °C. A sprinting swimmer, sometimes quarrelsome between males, it needs a long swimming lane and a single male or a female majority. An outstanding jumper needing a full lid and a tank at least 80 cm long, in moderately hard, well-oxygenated water.
100 litres minimum: why that number
For a group of 4+ Swordtail reaching 12 cm as an adult, plan 100 real litres — and remember a big tank is more STABLE, hence easier, than a small one: parameters drift slowly, leaving time to correct. This volume suits a sturdy standard cabinet — just verify perfect levelness.
Hardware: filter, heater, lighting
On hardware: a filter cycling the volume three to five times an hour, a heater around 1 W per litre set to 22 to 26°C, backed by an independent thermometer — built-in thermostats sometimes lie, and lighting on a timer at 8 to 10 hours a day: any longer and the algae win.
Substrate, plants and start-up
Nutrient substrate under fine sand or quartz, robust plants (anubias, vallisneria, Java moss) and wood to structure the territory. Then patience: a complete nitrogen cycle (3 to 4 weeks, nitrites back to zero) before the first Swordtail — the step every hurried beginner pays for dearly.
Frequently asked questions
What tank size for Swordtails?
A real 100 litres minimum for a group of 4+ — below that, parameters drift too fast to catch.
Does a Swordtail need a heater?
Yes, about 1 W per litre set to 22 to 26°C, with an independent thermometer double-checking the thermostat.
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