Hippocampus ingens
Pacific Seahorse (Hippocampus ingens) is a saltwater fish associated with Eastern Pacific, with a recorded adult length of up to 30 cm. This source-backed catalogue profile brings its essential aquarium planning information together on one page.
Temperature
24–27°C
pH range
8.1–8.4
Minimum tank
400 litres
Typical lifespan
10 years
Diet
Carnivore
Origin
Eastern Pacific
Adult size
Up to 30 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
Pacific Seahorse
Scientific name
Hippocampus ingens
Family
Syngnathidae
Family group
Pipefishes and seahorses
Water type
saltwater
Native range
Eastern Pacific
Social planning
Individual assessment
Conservation
Vulnerable (VU)
Aquarium setup
A mature marine aquarium with stable salinity, strong gas exchange and no detectable ammonia or nitrite. Measure salinity rather than estimating it.
Use 400 litres as the minimum planning baseline before allowing extra space for a group, tank mates, decor and swimming behaviour.
Hold temperature at 24–27°C and pH at 8.1–8.4; stability matters more than chasing a single number.
Design the aquarium around the recorded adult length of 30 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
Moderate waste load (0.6 index): allow spare biological capacity and service mechanical media before flow is restricted.
Feeding
Offer varied, appropriately sized animal-based foods. Confirm that the fish is eating and avoid relying on a single food long term.
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: A pinched belly, weight loss, weak feeding response or a fish being outcompeted at meals.
First response: Confirm that the fish accepts an appropriate food and can reach it without competition; seek help if weight loss continues.
Watch for: Hiding, faded colour, clamped fins, glass surfing, rapid breathing or appetite loss.
First response: Test water, review temperature and tank mates, reduce disturbance and correct problems gradually.
Before bringing one home
The established aquarium is at least 400 litres and matches the required saltwater system.
Temperature and pH overlap the full 24–27°C and 8.1–8.4 ranges.
A suitable carnivore 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 3284
Aquarium context
Present in the aquarium trade
Temperature basis
FishSnap tropical-marine planning baseline
pH basis
FishSnap marine 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
Alberto Alcalá · CC BY 4.0
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.
