All fish / Syngnathidae

Dwarf Seahorse

Hippocampus zosterae

Also known as dwarf seahorse, pygmy seahorse, zostera seahorse, dwarf sea horse, florida dwarf seahorse, ドワーフシーホース, 矮海马, 侏儒海马

This is one of the smallest seahorses, rarely longer than about 2.5 cm, and comes in beige, yellow, green or near black, sometimes with small skin filaments. Keepers like it because a whole colony fits in a small dedicated tank and its upright swimming and courtship are fascinating to watch.

Care at a glance

Care level

Hard

Temperament

Peaceful

Adult size

2.5 cm

Temperature

22 to 27 °C

pH

8.1 to 8.4

Smallest tank

20 litres

Keep as

Small colony; several pairs can share a dedicated tank

Diet

Carnivore: live newly hatched brine shrimp (enriched) and copepods, fed several times a day

Swims

Middle of the tank

Lifespan

1 to 2 years

Water

Marine (saltwater)

Wild range

Western Atlantic: Bermuda, Florida, Bahamas and the Gulf of Mexico

Breeding

Males carry the eggs in a brood pouch and release around 5 to 20 fully formed young after about 10 days. Breeding happens readily in a good setup, and the fry can eat newly hatched brine shrimp from birth, so raising them is easier than with most seahorses.

Good to know

They need constant live food and should only live in a species tank without filters that suck them in or tankmates that sting or outcompete them; hydroids and Aiptasia brought in with live food can kill them. Like all seahorses it is on CITES Appendix II, so check that stock is legally sourced or captive bred.