Family Reference
Livebearers
Poeciliidae — guppies, mollies, platies, and swordtails: matrotrophic fish that breed reliably in any tank that holds water.
The Complete Livebearers Guide: Guppies, Mollies & More
Field reference to livebearing aquarium fishes: Poeciliidae biology, internal fertilisation, hard-water husbandry, hybridisation, disease.
Read the guide →Species & Profiles
All articles in this section
Why Do My Guppies Keep Dying?
Chronic guppy mortality traces to farm-line inbreeding, mycobacteriosis, and water that is too soft or too cold. How to diagnose the cause in your tank, and what changes actually work.
Why Are My Mollies Shimmying?
Molly shimmying is a neuromuscular symptom of osmotic stress — usually soft water. Causes, diagnosis, and step-by-step correction including marine salt use, temperature, and water change protocol.
Four-eyed Fish (Anableps anableps): Brackish Surface Specialist
Field profile of Anableps anableps: identification, hard-water parameters, behaviour, diet, breeding, tankmates, and common aquarium problems.
Common Molly (Poecilia sphenops): Freshwater or Brackish?
Field profile of Poecilia sphenops: identification, hard-water parameters, behaviour, diet, breeding, tankmates, and common aquarium problems.
Swordtail (Xiphophorus hellerii): Size, Sexing & Care
Field profile of Xiphophorus hellerii: identification, hard-water parameters, behaviour, diet, breeding, tankmates, and common aquarium problems.
Endler's Livebearer (Poecilia wingei): Pure vs Hybrid Care
Field profile of Poecilia wingei: identification, hard-water parameters, behaviour, diet, breeding, tankmates, and common aquarium problems.
Variatus Platy (Xiphophorus variatus): Cooler Hard-Water Care
Field profile of Xiphophorus variatus: identification, hard-water parameters, behaviour, diet, breeding, tankmates, and common aquarium problems.
Wrestling Halfbeak (Dermogenys pusilla): Surface Livebearer Care
Field profile of Dermogenys pusilla: identification, hard-water parameters, behaviour, diet, breeding, tankmates, and common aquarium problems.
Pike Livebearer (Belonesox belizanus): Predatory Livebearer Care
Field profile of Belonesox belizanus: identification, hard-water parameters, behaviour, diet, breeding, tankmates, and common aquarium problems.
Balloon Molly (Poecilia sphenops): Welfare and Care Limits
Field profile of Poecilia sphenops: identification, hard-water parameters, behaviour, diet, breeding, tankmates, and common aquarium problems.
Sailfin Molly (Poecilia latipinna): Brackish-Tolerant Care
Field profile of Poecilia latipinna: identification, hard-water parameters, behaviour, diet, breeding, tankmates, and common aquarium problems.
Mosquitofish (Gambusia affinis/holbrooki): Care & Cautions
Field profile of Gambusia affinis/holbrooki: identification, hard-water parameters, behaviour, diet, breeding, tankmates, and common aquarium problems.
Black Molly (Poecilia sphenops): Melanistic Molly Care
Field profile of Poecilia sphenops: identification, hard-water parameters, behaviour, diet, breeding, tankmates, and common aquarium problems.
Platy (Xiphophorus maculatus): Care & Colour Forms
Field profile of Xiphophorus maculatus: identification, hard-water parameters, behaviour, diet, breeding, tankmates, and common aquarium problems.
Guppy (Poecilia reticulata): Care, Lines & Disease
Field profile of Poecilia reticulata: identification, hard-water parameters, behaviour, diet, breeding, tankmates, and common aquarium problems.
Dalmatian Molly (Poecilia sphenops): Spotted Molly Care
Field profile of Poecilia sphenops: identification, hard-water parameters, behaviour, diet, breeding, tankmates, and common aquarium problems.
Limia (Limia spp.): Caribbean Livebearer Care
Field profile of Limia spp.: identification, hard-water parameters, behaviour, diet, breeding, tankmates, and common aquarium problems.
Least Killifish (Heterandria formosa): Tiny Matrotrophic Livebearer
Field profile of Heterandria formosa: identification, hard-water parameters, behaviour, diet, breeding, tankmates, and common aquarium problems.