Knight Goby
Stigmatogobius sadanundio
Brackish South Asia
An attractive, predatory goby adorned with metallic sheen and black leopard-like spotting. Although sold as freshwater, it fares far better in low-end brackish aquariums. It will readily swallow bite-sized fish and shrimp, so house it solely with robust, peaceful brackish tank mates.
Try it in the planner Opens a tank sized to its minimum with 1 fish added.
What it needs
| Item | Value | Because |
|---|---|---|
| Adult length | 8 cm | Used for the Space check: the tank must be long enough for the fish to turn round. |
| Smallest tank | 80 L, at least 60 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 | 15 L estimated | What each further fish adds once the minimum is met. |
| Waste load | Class 2 of 5 estimated | How much waste an adult makes against its size. Feeds the Load check. |
| Temperature | 22 to 27 C | Stock sharing a tank need overlapping ranges. |
| pH | 7.5 to 8.5 | Compared with tankmates in the Water check. |
| Hardness | GH 10 to 25, KH 6 to 15 | 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 | Semi-aggressive | Territorial: weak. |
| Swims in | Near the bottom | Fish that use different levels share a tank more easily. |
| Lifespan | About 4 years | A fish is a long commitment. |
| Experience | Some experience helps | A guide to how forgiving the species is of mistakes. |
| Jumps | Yes | Keep the tank covered. |
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
Knight Goby 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
Depends
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.