Midas Blenny Care Guide (2026)

Midas Blenny Care Guide (Ecsenius midas)

The Midas Blenny is one of the most striking and personable small reef fish in the marine hobby. Named for its vivid golden-yellow coloration — which can shift to blue-purple depending on mood and environment — it is peaceful, reef-safe, and an excellent fit for community reef tanks. Unlike many blennies, the Midas is primarily a planktivore rather than an algae grazer, which gives it a distinct feeding niche and makes it a different kind of addition to a reef than the Tailspot Blenny.

Species Overview

  • Scientific name: Ecsenius midas
  • Common name: Midas Blenny, Golden Blenny, Persian Blenny
  • Origin: Indo-Pacific, Red Sea
  • Adult size: 4–5 inches
  • Lifespan: 4+ years with good care
  • Experience level: Beginner–intermediate
  • Temperament: Peaceful with most species; can be territorial toward similar-looking fish
  • Diet: Planktivore; primarily zooplankton and small meaty foods in captivity
  • Tank level: Mid-water and rockwork surfaces
  • Reef safe: Generally yes — see below

Tank Size

A 30-gallon tank is a workable minimum for a single Midas Blenny. The fish reaches 4–5 inches and is more active than many small reef fish, spending time both perching on rockwork and swimming in the mid-water column. A larger tank — 40 gallons or more — is preferred for a community setup.

→ Midas Blenny Tank Size Guide | Best Saltwater Aquarium Tanks

Water Parameters

  • Temperature: 72–78°F (22–26°C)
  • Salinity: 1.020–1.025 SG
  • pH: 8.1–8.4
  • Ammonia/Nitrite: 0 ppm
  • Nitrate: As low as possible; below 20 ppm preferred

→ Best Reef Test Kits

Diet and Feeding

The Midas Blenny is primarily a planktivore — it feeds on zooplankton in the water column rather than grazing algae from rockwork surfaces. In captivity it accepts:

  • Frozen mysis shrimp — the most reliable staple
  • Frozen brine shrimp (enriched preferred)
  • Small carnivore or omnivore pellets
  • Copepods and amphipods

Feed once or twice daily. The Midas Blenny will actively swim into the water column to intercept food.

→ Midas Blenny Feeding Guide

Behavior and Personality

Midas Blennies are active, curious fish with a lot of personality. They perch on rockwork and will often follow the keeper's movements at the glass. They are more active swimmers than most blennies and spend significant time in the mid-water column, particularly during feeding. Coloration can shift from vivid golden-yellow to blue-purple depending on mood, stress, and environment — this is normal and not a sign of illness.

Tankmates

Midas Blennies are peaceful with virtually all community reef fish. They can show territorial behavior toward other blennies or similarly shaped fish, particularly in smaller tanks. Keep only one Midas Blenny per tank unless the system is large enough to support separate territories.

→ Midas Blenny Tankmates Guide

Reef Safety

Midas Blennies are generally reef-safe. Some individuals have been reported to nip at LPS corals or clam mantles — this is not universal behavior but is worth monitoring, particularly when newly introduced.

→ Is the Midas Blenny Reef Safe?

Midas vs Tailspot Blenny

The Midas Blenny is frequently compared to the Tailspot Blenny. Key differences: Midas is larger, more active in the water column, and primarily planktivorous; Tailspot is smaller, more rockwork-bound, and an active algae grazer. Both are good community reef fish but fill different niches.

→ Midas Blenny vs Tailspot Blenny

Not Eating or Hiding

Newly introduced Midas Blennies may hide for several days while acclimating. This is normal. If an established fish stops eating, check water parameters first.

→ Midas Blenny Not Eating or Hiding

Setup Summary

  • Tank: 30 gallons minimum; 40+ gallons preferred for community setups
  • Diet: Planktivore — frozen mysis, brine shrimp, small pellets
  • Reef safe: Generally yes; monitor with LPS corals and clams
  • Keep one per tank unless system is large

Full Midas Blenny Guide Index

Gear Guides

Related Species Guides