Home / Fishes / Gobies and sleepers / Olive flathead-gudgeon
No federal permit to keepOlive flathead-gudgeon
Butis amboinensis
Fishes › Gobies and sleepers (Gobiiformes) › Butidae (Sleeper gudgeons)
Care follows the sleeper gudgeons guide below.
Care at a glance
Species-specific aquarium care
- Tank: At least 24 in long and 12 in front to back for one adult (adults commonly reach about 5.5 in / 14 cm).
- Water: Freshwater (tolerates brackish).
- Temperature: 72–82°F (range recorded for this species).
- Layout: Lives on or near the bottom: floor space and hiding places matter more than height.
Calculated from this species' own FishBase record: tank size from its typical adult length and swimming zone, water values from its recorded ranges. The group guide below fills in general care.
Care guide
Species care notes
- Tank: a base of at least 30 × 12 in (roughly 18 US gallons); space needed is rated “modest tank”.
- Water: a fairly wide range, from slightly acidic to slightly alkaline, 72–82 °F, pH 7–8.5, 8–20 dGH.
- Behaviour: temperament territorial; kept alone; not a community fish.
- Difficulty: Easy (Seriously Fish rating).
Short excerpts from the species profile:
- Setup: “Best-maintained in brackish water although the precise specific gravity is unimportant provided it does not exceed that of seawater (1.025).”
- Diet: “This species is an ambush predator feeing mostly on smaller fishes, worms, and crustaceans in nature.”
- Tankmates: “Territorial and may react aggressively towards related or similarly-shaped species, while smaller fishes and invertebrates will be preyed upon.”
- Breeding: “Unlikely to have been bred in captivity.”
From the Seriously Fish profile for this species, which has the full habitat, maintenance, diet, behaviour and breeding write-up 167
Sleeper gudgeons
Applies to most species in this group. Habitat: These bottom-oriented predators inhabit Indo-Pacific rivers, ponds and flooded forests or coastal estuaries and mangroves, often sheltering among roots and vegetation. [fg277-marble, fg277-olive, fg277-mud]. Individual species can differ, so compare with the species numbers above and the linked sources.
Housing & setup
- For one Butis amboinensis, provide at least a 75 × 30 cm footprint; use larger quarters for companions.
- For O. marmorata, the cited starting adult enclosure is 150 × 60 × 60 cm, approximately 540 litres; the largest specimens require more space.
- Give marble gobies several inches of soft sand for digging and partial burial; sand also avoids gravel ingestion by Butis.
- Provide substantial root, pipe or pot retreats and subdued lighting.
- Keep Butis in brackish water matched initially to the supplier; do not exceed seawater SG 1.025. Marble gobies are primarily freshwater inhabitants.
Climate & lighting
| Water | 71.6–82.4°F |
Diet
- Bloodworms and small earthworms for juveniles.
- Whole prawns and appropriately sized fish for larger marble gobies.
- Shrimp, mussel or squid flesh for Butis.
- Mysis or Artemia for suitably sized Butis; meat-based pellets may be accepted by trained marble gobies.
Social life
- Keep Butis and marble gobies singly unless very large housing and compatible large tankmates are available; both can be territorial and swallow smaller fish.
Health watch
- Nutritional disease from inappropriate mammalian or avian meat.
- Parasites introduced with feeder fish.
- Ammonia toxicity.
Understanding the animal
In the wild
In the wild
From this species’ own FishBase record (habitat, bottom type, water and breeding data), not its family. Good care copies these conditions.1
| Where it lives | Lives in freshwater and brackish water and the sea, in rivers and streams, estuaries, mangroves. Stays near the bottom. This species is reported to occur in many coastal streams in brackish to freshwaters and estuaries over substrates of mud, sandy mud or leaf litter and is often observed clinging upside down under dead wood, eyes facing downwards. An ambush hunter, feeding mainly on small fish and crustaceans (shrimps (Atyidae), prawns (Palaemonidae)). |
| Ground it lives on | Over sand, mud. |
| Water it lives in | Freshwater / brackish water / marine, 72–82 °F (22–28 °C), depth 0–5 m. |
| Climate | Tropical climate. |
What this means for care
- Keep water within its wild range, 72–82 °F.
- Use a soft, fine bottom; it lives over fine sediment in the wild.
- It tolerates or needs brackish water; check salinity needs before setup.
Native climate (measured)
Native climate (measured)
| Warm-season highs | about 88°F (up to 90°F in the hottest sampled areas) |
| Cool-season lows | about 70°F (down to 59°F in the coldest sampled areas) |
| Average temperature | 73–81°F across sampled records |
| Relative humidity | 80–83% on average (driest month about 79%) |
| Rainfall | about 2332 mm a year, spread fairly evenly |
Measured at 49 wild occurrence records sampled against WorldClim 2.1 climate data (1970–2000 averages). Air conditions in the range are ecological context, not enclosure settings: microhabitats such as burrows, leaf litter or basking rocks can be cooler, warmer or more humid.
From the sources
From the sources
Quoted from the matching sections of reputable sources for this exact species. Specialist databases are used first; Wikipedia (community-edited, CC BY-SA 4.0) only fills gaps. Other sources are short credited quotes.
| Where it lives | Home ranges Population dynamics Growth parameters Max. ages / sizes Length-weight rel. Length-frequencies Mass conversion Recruitment Abundance Life cycle Reproduction Maturity Maturity/Gills rel. — FishBase |
| Biology | This species is reported to occur in many coastal streams in brackish to freshwaters and estuaries over substrates of mud, sandy mud or leaf litter and is often observed clinging upside down under dead wood, eyes facing downwards. — FishBase |
Data and studies
The numbers
The numbers
Each bar is what one source reports. Where several sources weigh in, the dashed gold band marks their average.
Adult length
Maximum recorded length. Measured as standard length (snout to the base of the tail, not counting the tail fin). Fish in home aquariums often stay smaller than wild records.
Water temperature
Range the species tolerates in nature; aim for the middle.
pH
Water hardness
Minimum tank footprint
Seriously Fish recommends a tank base of at least 30 × 12 in (about 18 US gallons).
Sources for this sheet
- FishBase (Froese & Pauly, eds.), version 24.07 Peer-reviewed researchThe global scientific database on fishes, maintained by a consortium of research institutions; every value is referenced.
- Seriously Fish species profiles Experienced keeper or breederLong-running aquarium reference written and peer-checked by experienced fishkeepers and ichthyologists; each profile covers habitat, tank size, water, diet, behaviour and breeding.
- Seriously Fish — Oxyeleotris marmorata Experienced keeper or breederAdded in the 2026 source-checked care-guide review.
- Seriously Fish — Butis amboinensis Experienced keeper or breederAdded in the 2026 source-checked care-guide review.
- FishBase — Northern mud gudgeon, Ophiocara porocephalum, citing the 2021 genus revision Peer-reviewed researchAdded in the 2026 source-checked care-guide review.
- Merck Veterinary Manual — Disorders and Diseases of Fish Zoo, university or veterinaryAdded in the 2026 source-checked care-guide review.
