🐠Killifish: gear and buying guides

Killifish, such as Aphyosemion australe, are small, brilliantly colored fish often content with 20 to 50 L tanks. Many prefer soft, slightly acidic and rather cool water, between 20 and 24 °C, with subdued lighting. Outstanding jumpers, they demand a lid with no gaps at all; some annual species have naturally short lifespans.

Profile : 4 to 6 cm as an adult depending on the species, 20 to 50 L depending on the species, water between 20 and 24 °C.

Killifish gear, family by family

• 🍖 Food

  A surface carnivore that prefers live and frozen foods: brine shrimp, daphnia, grindal worms. Many killifish snub dry flakes, so keep a stock of frozen food.

• 🧴 Care & grooming

  Soft, slightly acidic water without elevated nitrates, often softened with RO water. Constantly warm temperatures noticeably shorten its lifespan.

• 🎾 Toys & enrichment

  Floating plants, Java moss and a dark substrate show off its colors and reassure it. A synthetic-yarn spawning mop encourages breeding behavior.

• 🏠 Bedding & habitat

  A 20 to 50 L tank depending on the species, gently filtered, often kept species-only with one male and two or three females. A gap-free lid is the number one safety point.

• 🧳 Travel & safety

  It jumps the moment the bag opens: handle it above a closed surface and transfer carefully. Slow 30 to 45 minute acclimation, especially into harder water.

• 🧰 Accessories

  A sponge filter, a snug lid, peat or catappa leaves for acidifying and a spawning mop. A small budget of around 60 to 120 euros for a complete species tank.

Guides to read

• 60-litre aquarium kit: the full beginner budget with no nasty surprisesBedding & habitat

  How much does a 60-litre aquarium kit really cost? The full start-up budget, item by item: equipped tank, substrate, decor, water tests and consumables.

• Nano shrimp tank: the essential equipment to start off rightBedding & habitat

  What equipment does a nano shrimp tank need? Volume, gentle filtration, the right substrate and a full budget: the complete checklist for keeping Neocaridina.

• Betta tank of 20-30 litres: the ideal setup, step by stepBedding & habitat

  How do you set up a 20 to 30 litre betta tank? Low-flow filtration, heating, resting plants and a lid: the ideal setup explained in detail.

• Garden pond for goldfish: volume, equipment and budgetBedding & habitat

  How do you build a garden pond for goldfish? Minimum volume, frost-free depth, filtration and predator protection: the complete guide with budget.

• RO units and reverse osmosis water in aquariums: who actually needs it?Care & grooming

  Is reverse osmosis water essential for an aquarium? Find out who really needs an RO unit, how to remineralize and what budget to plan (unit or jerrycan).

• Water conditioner and starter bacteria: essential or just marketing?Care & grooming

  Water conditioner and starter bacteria: what do they actually do? Chlorine, heavy metals, faster cycling: what to buy and what to skip.

• Fertilizer and CO2 for aquarium plants: start simple, skip the lab setupToys & enrichment

  Do aquarium plants need fertilizer and CO2? The simple starter method: liquid fertilizer, easy plants, and when injected CO2 actually becomes worthwhile.

• Driftwood and rocks for aquariums: which ones are safe for your fish?Toys & enrichment

  Which driftwood and rocks are safe in an aquarium? Tannin-releasing woods, limestone rocks to avoid, the vinegar test and preparation: the complete guide.