Snake Pipefish Entelurus Aequoreus

Snake Pipefish (Entelurus aequoreus)

(Also known as the Northern Pipefish or Sea Grass Pipefish)

Overview

The Snake Pipefish is a long, slender species resembling a stretched-out seahorse, with a serpentine body that can reach up to 45–60 cm (18–24 inches) in length. It is the largest European pipefish and a relative of the seahorse, belonging to the family Syngnathidae. Its colour varies from pale green to brown, often patterned with faint stripes or mottling that helps it blend perfectly into seagrass or kelp. Though fascinating, this species is difficult to maintain in captivity, requiring cool, pristine, and naturally rich environments.

Origin

Native to the Eastern Atlantic Ocean, ranging from Norway and the British Isles to Portugal and the Mediterranean, as well as parts of the North Sea and Baltic. It inhabits shallow coastal waters, seagrass beds, eelgrass meadows, and kelp forests, often in cooler temperate conditions.

Feeding

The Snake Pipefish is a specialised micro-carnivore, feeding on tiny planktonic crustaceans and larvae in the wild. In captivity, feeding is one of the biggest challenges:

• Live copepods and amphipods (essential)
• Live enriched baby brine shrimp
• Live mysis shrimp or small feeder shrimp (as supplemental food)
• Frozen foods are rarely accepted unless the individual is trained

Feed multiple small meals daily to maintain body condition. A mature, pod-rich aquarium or coldwater refugium is essential for long-term success.

Tank Mates

This is an extremely peaceful and slow-moving species that should only be housed with other gentle, non-competitive fish. Suitable companions include:

• Coldwater gobies and blennies (temperate species)
• Seahorses and other pipefish (if temperature and space allow)
• Passive invertebrates such as snails or small crabs

Avoid any active or warmwater tropical species — the Snake Pipefish thrives only in cool, calm environments.

Aggression

Completely peaceful. They can be kept singly or in pairs, occasionally forming loose groups in larger, naturally enriched systems. Males carry eggs along the underside of the tail.

Experience Level

Expert only. Due to its coolwater requirements, specialised diet, and size, the Snake Pipefish is not suited for standard tropical marine aquariums. It is best maintained in dedicated coldwater marine systems by experienced aquarists or public aquariums.

Water Parameters

• Temperature: 12–18°C (54–64°F)
• pH: 8.0–8.3
• Salinity: 1.022–1.025 SG
• Hardness (dKH): 7–11
• Tank Size: Minimum 150 gallons (570L) for an adult pair or group

Provide gentle water flow, abundant macroalgae or seagrass, and plenty of hiding areas to replicate their natural habitat.

Reef Compatibility

Not reef suitable. The Snake Pipefish is a temperate species, unsuited to tropical reef temperatures. However, it can be safely kept in coldwater marine displays with macroalgae, sponges, and other temperate invertebrates.