Sharknose Goby (Elacatinus evelynae)

Sharknose Goby (Elacatinus evelynae) Care Guide

The Sharknose Goby, scientifically classified as Elacatinus evelynae, is a brilliant and highly functional resident of the Caribbean coral reefs. Belonging to the family Gobiidae, this miniature specialist reaches a maximum total length of just 5 cm (2 inches), making it one of the most anatomically suitable and visually striking candidates for nano reef setups. Characterized by a sleek, dark body adorned with a bold, contrasting lateral stripe that shifts from electric blue to neon yellow depending on its geographical population variant, this species is immediately recognizable. Far beyond its aesthetic value, its highly evolved, mutualistic cleaning behavior provides a genuine ecological service, actively working to keep its fish tank mates healthy and vibrant.

Aquarium Conditions

The Sharknose Goby is exceptionally adaptable, requiring a minimum aquarium volume of 40 liters (10.6 gallons) for a single specimen or an established pair, though a larger saltwater aquarium provides a superior chemical safety buffer. The structural foundation of the layout must prioritize complex, porous live rock formations with numerous deep crevices, small overhangs, and macro-voids to mimic their natural Caribbean micro-habitats. Water parameters must remain highly stable, adhering to the following professional reef targets: temperature at 22.5–25.5°C (72.5–78°F), pH at 8.1–8.4, salinity at 1.020–1.025 sg, and alkalinity maintained between 8–12 dKH.

Moderate, multidirectional water movement is ideal; aggressive, unidirectional laminar flow directed at their preferred perching rocks should be avoided as it disrupts their stable hovering and cleaning posture. Furthermore, while they originate from shallow reef slopes, intense blue-spectrum LED lighting exceeding 250 PAR at their home station should be avoided, as prolonged exposure can cause their distinctive crimson eye pigmentation to gradually fade. A patient, 45–60 minute drip acclimatization protocol is mandatory to safeguard them from osmotic shock, and the individual should always be transferred via a water-filled cup instead of a net to prevent damage to its sensitive, protective epidermal mucus barrier.

Nutrition

As a specialized carnivore, Elacatinus evelynae has evolved a diet primarily focused on harvesting ectoparasites, dead epithelial tissue, and excess mucus from client fish at dedicated cleaning stations. In the saltwater aquarium, especially when utilizing captive-bred specimens (such as those produced by ORA), they readily transition to prepared commercial diets. Their daily nutritional regimen should consist of high-quality frozen mysis shrimp, vitamin-enriched artemia nauplii, and frozen copepod or amphipod blends.

Because they possess a small mouth cavity, all foods must be finely crushed or sized under 1 mm to ensure successful ingestion. Due to their high benthic metabolic rate, feeding small portions twice daily is highly recommended. Utilizing a target-feeding pipette to deliver foods directly to their preferred rock station is an excellent management strategy to ensure they are not outcompeted by aggressive or fast-swimming upper-water aquarium inhabitants.

Behavior and Compatibility

The Sharknose Goby is famous for its intricate cleaning station etology, a symbiotic behavior where client fish approach the goby’s perch and adopt stationary, non-threatening invitation postures (such as flared gills and vertical hovering) to signal their readiness for cleaning. They are exceptionally peaceful and 100% reef-safe, posing absolutely no threat to stony corals, soft corals, clams, or ornamental invertebrates. While docile toward unrelated families, they exhibit substrate-attached territoriality and can show intense intraspecific aggression toward other Elacatinus gobies over physical cleaning territory if housed in cramped spaces.

To safely keep multiple non-paired individuals, provide an aquarium volume of at least 100 liters (26.4 gallons) with visually isolated rock clusters. Ideal companion species include firefish, small clownfish, cardinalfish, and peaceful flasher wrasses. Avoid housing them with large, opportunistic predators such as hawkfish, lionfish, or large groupers that could readily view this miniature goby as an easy food source.

Breeding Behavior

In their natural habitat, Elacatinus evelynae forms strong monogamous pairs that engage in a substrate-spawning reproductive strategy. Once a secure spawning site is located under a rocky ledge or inside a clean, narrow crevice, the female deposits a cluster of adhesive eggs. The male exclusively assumes a paternal nest-guarding role, aggressively protecting the site and continuously fanning the egg mass with his pectoral fins to maintain constant oxygenation until hatching occurs, typically within 7 to 10 days.

Captive breeding in a standard home aquarium is rare and technically demanding due to the microscopic, highly sensitive nature of the planktonic larva phase, which lasts approximately 15 to 25 days. Successfully rearing the fry requires a dedicated larval tank, microalgae conditioning (green water technique), and a reliable, dense culture of live rotifers (Brachionus sp.) followed by artemia nauplii to sustain the young through metamorphosis until they successfully settle onto the benthic substrate.

Health and Diseases

While traditionally recognized as a resilient and disease-resistant species under stable parameters, the Sharknose Goby is highly vulnerable to sudden environmental fluctuations. Rapid changes in temperature or salinity can cause acute cortisol-driven stress, inducing immunosuppression and leaving them susceptible to common marine pathogens such as Marine Ich (Cryptocaryon irritans) and Saltwater Velvet (Amyloodinium ocellatum).

Implementing a strict 4-week quarantine protocol in a separate system for all new wild-caught arrivals is essential to safeguard the health of your display reef. Furthermore, ensure that any adjacent rockwork or artificial breeding tubes are smooth and free of sharp edges to eliminate the risk of physical abrasions, which can easily lead to secondary bacterial dermatitis or fluid-filled ulcers. Regular weekly 10–15% water changes are strongly advised to keep dissolved organic compounds low and maintain pristine water quality.

Cover Photo Credit: Reef Casa

References:

1. ORA: Sharknose (Elacatinus evelynae) / Last Accessed Date: 23.03.2026
2. Wikipedia: Elacatinus evelynae / Last Accessed Date: 23.03.2026
3. FishBase: Elacatinus evelynae (Böhlke & Robins, 1968) / Last Accessed Date: 23.03.2026