Fundulus luciae
Spotfin Killifish (Fundulus luciae) is a brackish fish associated with Western Atlantic, with a recorded adult length of up to 5 cm. This source-backed catalogue profile brings its essential aquarium planning information together on one page.
Temperature
18–24°C
pH range
7.5–8.4
Minimum tank
50 litres
Typical lifespan
4 years
Diet
Omnivore
Origin
Western Atlantic
Adult size
Up to 5 cm
Care level
Care level recorded in the source-backed catalogue profile.
Aquarium context
Present in the aquarium trade
Check it against your aquarium before purchase, then use the complete preparation checklist below.
Check compatibilitySpecies identity
Common name
Spotfin Killifish
Scientific name
Fundulus luciae
Family
Fundulidae
Family group
Topminnows and killifishes
Water type
brackish
Native range
Western Atlantic
Social planning
Individual assessment
Conservation
Least concern (LC)
Aquarium setup
A dedicated brackish aquarium. Mix marine salt with conditioned water and measure the result consistently; ordinary tonic salt is not a substitute.
Use 50 litres as the minimum planning baseline before allowing extra space for a group, tank mates, decor and swimming behaviour.
Hold temperature at 18–24°C and pH at 7.5–8.4; stability matters more than chasing a single number.
Design the aquarium around the recorded adult length of 5 cm, not the juvenile size seen at purchase.
Provide retreat areas and visual breaks while preserving enough unobstructed space for normal movement and feeding.
Filtration & waste
Lower individual waste load (0.2 index), but group size and total stocking still determine the filter capacity required.
Feeding
Use a varied omnivore staple with complementary plant and animal ingredients. Feed controlled portions and adjust to body condition and waste production.
Observe
Confirm every fish reaches food and swallows it.
Control
Stop before leftovers can decay in the aquarium.
Review
Track body condition, waste and feeding response over time.
Behaviour & tank mates
Treat temperament as an individual assessment. Observe feeding and territorial behaviour, and keep a safe separation plan available.
No simple community match is approved in this profile. Plan species-only housing or obtain a specialist compatibility assessment before adding tank mates.
Health watch
These are risks to monitor, not diagnoses. Test the aquarium first and seek an aquatic vet or experienced specialist for severe, fast-moving or uncertain symptoms.
Watch for: Rapid breathing, lethargy, erratic swimming or decline after a salinity or water-chemistry change.
First response: Measure salinity and water chemistry, then correct any mismatch gradually rather than making another sudden change.
Watch for: Rapid breathing, surface gasping, clamped fins, lethargy or several fish declining together.
First response: Test ammonia, nitrite, nitrate, pH and temperature immediately and correct unsafe values gradually.
Before bringing one home
The established aquarium is at least 50 litres and matches the required brackish system.
Temperature and pH overlap the full 18–24°C and 7.5–8.4 ranges.
A suitable omnivore food is available and the seller can demonstrate that the fish is feeding.
Ammonia and nitrite test at zero, acclimation is planned and a quarantine or observation option is ready.
Every proposed tank mate has been screened for adult size, behaviour, feeding competition and water compatibility.
Data & source notes
Catalogue source
FishBase · release 26.07
Species record
FishBase SpecCode 3195
Aquarium context
Present in the aquarium trade
Temperature basis
FishSnap temperate-freshwater planning baseline
pH basis
FishSnap brackish planning baseline
Tank basis
FishSnap conservative planning baseline derived from adult size, water type, social ecology and family
Lifespan basis
FishSnap size/family planning estimate
Photo credit
Scott Smith · CC0
FishBase remains an editorial reference, but the useful species and care information is interpreted here so you do not have to leave FishSnap. Conservative planning baselines are labelled as guidance, not guarantees.
