Get a Huge Tank

All fish

Green Wolf Eel

Congrogadus subducens

Marine Marine Indo-Pacific

Despite its common name, this elongated marine oddball is actually an eel-blenny related to dottybacks. It possesses inquisitive eyes and mottled green skin, weaving through rockwork like a serpent. Keepers must provide a secure, gap-free lid, as these crafty predators will readily slither through any opening.

Also called: Ambeetunbeet, Carpet conger blenny, Carpet eel blenny, Carpet eel-blenny.

35 cm adult length, drawn to scale. eel body.

Outgrows a typical home tank. Check this fish against the adult size above before buying a juvenile. The minimum shown is the least it is kept in for good, not a comfortable size.
Saltwater species. The planner judges it with a marine rule set. A reef or fish-only tank takes months to mature and costs more to run than freshwater. See the marine page.

Try it in the planner Opens a tank sized to its minimum with 1 fish added.

What it needs

ItemValueBecause
Adult length 35 cm Used for the Space check: the tank must be long enough for the fish to turn round.
Smallest tank 300 L, at least 120 cm long estimated The least water and floor length this species is kept in for good, as a single fish or smallest group.
Extra water per added fish 80 L estimated What each further fish adds once the minimum is met.
Waste load Class 4 of 5 estimated How much waste an adult makes against its size. Feeds the Load check.
Temperature 24 to 28 C Stock sharing a tank need overlapping ranges.
pH 8.1 to 8.4 Compared with tankmates in the Water check.
Hardness GH 8 to 12, KH 8 to 12 Degrees of general and carbonate hardness.
Flow Medium Low-flow fish are stressed in a strong current.
Light Moderate Matched to the lighting class on the needs sheet.
Group size Single fish is fine Not a schooling species.
Temperament Predator Territorial: strong.
Swims in Near the bottom Fish that use different levels share a tank more easily.
Lifespan About 10 years A fish is a long commitment.
Experience Suits a first tank A guide to how forgiving the species is of mistakes.
Jumps Yes Keep the tank covered.
Salinity Marine, about SG 1.023 to 1.025 Needs salt water, a different build and a longer-running tank than a freshwater set-up.

Tags marked estimated are judged from the size and habits of the species rather than measured, so treat them as a sensible default.

Diet and tank layout

Green Wolf Eel is an carnivore that swims in the lowest part of the tank. It is safe with plants. Give it plenty of cover. It will eat fish small enough to swallow.

Tankmates

Works with

Depends

Avoid

Compare any two fish on the compatibility page, or print the equipment for a stock on the needs sheet. How this is worked out: the method.