Royal Gramma
Gramma loreto
Purple-and-gold peaceful reef bassletBeginner
- Lifespan
- 5-7 years
- Size
- 8 cm (3 in)
- Social needs
- Best kept singly; territorial with own kind
- Time
- Daily feeding; weekly testing/changes
- Cost
- Medium
- Diet
- Carnivore (mysis, brine, marine pellets)
Overview
What is this animal?
- The Royal Gramma is a small basslet split vividly into magenta-purple at the front and golden-yellow at the rear.
- Hardy, peaceful toward unrelated fish, and reef-safe, it is a good colourful beginner marine fish.
- It darts among rockwork and often hangs upside-down beneath ledges.
- It comes from Caribbean reef caves and appreciates plenty of hiding spots.
- A well-fed Royal Gramma is shy at first but soon becomes confident, claiming a favourite cave and defending it with mostly harmless bluster against passing tankmates.
Temperament
- Peaceful toward unrelated species, the Royal Gramma is territorial mainly around its chosen cave, where it bluffs and posts largely harmless threats.
- It is reef-safe and ignores corals and invertebrates.
- Keep one per tank unless the system is very large with widely separated territories, as they fight their own kind and the similar-looking Royal Dottyback.
- With peaceful tankmates and good cover it is a confident, characterful resident.
A good fit for
- Beginners wanting vivid colour
- Peaceful community reef tanks
- Smaller marine setups
- Keepers who enjoy cave-dwelling behaviour
Common mistakes to avoid
- Keeping multiples in small tanks (fighting)
- Confusing it with the aggressive Dottyback
- No caves or hiding spots causes stress
- Open-top tank leads to jumping
Enclosure
Minimum 110 litres (29 US gallons)
Must be housed alone. Best kept singly; territorial with own kind
- A cycled 110L (30 gal) tank with abundant live rock, caves, and overhangs lets it feel secure.
- Maintain salinity 1.024-1.026, temperature 24-27°C (75-80°F), pH 8.1-8.4, and nitrate under 20 ppm.
- A lid is essential, as they readily jump from open tanks.
- Provide line-of-sight breaks with rock so it can establish a home base without stress.
- The more caves and crevices available, the bolder and more visible it becomes, since it always wants an escape route close at hand.
Supplies
Setup
- Tank, stand and sump
- Return pump and powerheads
- Protein skimmer
- Reef lighting
- Rock and sand
- Salt mix, refractometer and test kits
- Quarantine tank
Ongoing
- Frozen mysis shrimp
- Frozen enriched brine shrimp
- Small sinking marine pellet
- Frozen chopped seafood blend
- Vitamin or HUFA soaking supplement
- Turkey baster for target-feeding near rockwork
- Small thawing cup and strainer
Safe substrate: Aragonite sand · Dry or cured live rock · Bare bottom
Care routine
Daily
- Check salinity, temperature and flow
- Check the lid
- Feed
- Head-count and look everyone over
- Top up evaporation with fresh water
Weekly
- Service the skimmer and filter socksevery 3 days
- Check each fish still has a cave
- Clean the glass
- Test the water
Monthly
- Water changeevery 2 weeks
- Calibrate the refractometer
- Check salt, RO/DI and reagents
Less often
- Deep-clean pumps and powerheadsevery 3 months
- Replace RO/DI filter mediaevery 6 months
Vet: Quarterly review with a territory check — every 3 months
Top resources for more info
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Diet
- The Royal Gramma is a carnivore that in the wild eats zooplankton and small crustaceans.
- In the aquarium offer frozen mysis and brine shrimp, finely chopped seafood, and a sinking marine pellet, fed once or twice daily.
- Most specimens feed readily within days of settling in.
- A varied meaty diet keeps the purple and gold colours strong.
- Feed modest amounts to avoid fouling the water, and make sure faster tankmates do not take all the food first.
Health
- Royal Grammas are hardy and relatively disease-resistant in stable water.
- The main risks are marine ich and bacterial infections following stress, poor water quality, or aggression from tankmates or a rival Dottyback.
- Quarantine new arrivals and keep nitrate low and parameters steady.
- Watch for hiding, refusing food, or white spots as early warning signs.
- A secure, cave-rich tank reduces stress and keeps this basslet healthy for years.
Is your enclosure big enough?
Is this urgent?
In a reef, stability matters more than any single target number. A parameter moving fast does more damage than a parameter sitting slightly off.
Go now
Today
Quarantine every new animal, including corals and inverts. It is the single practice that separates a reef that lasts from a reef that restarts.
This is general guidance for a healthy adult, not a diagnosis. An exotics vet who knows your animal always overrides it — and the time to find one is before you need one.
What it really costs
Setup, monthly, first year and across a whole life, itemised and with the electricity worked out from the actual wattage. Published figures for the same animal disagree by a factor of four, so the calculator shows ranges rather than picking one.
Bedding and substrate
In a marine system the rock and the sand are life support, and how you start them decides the first six months.
Safe
With a caveat
Never
This is our general list for saltwater fish. We have not built one specific to Basslets yet.
My kit says 0.25 ppm. Is that dangerous?
A liquid kit measures total ammonia, but only the un-ionised fraction is really toxic, and that fraction is governed by pH and temperature — each whole pH unit multiplies it roughly tenfold. So the same reading can be nearly harmless in one tank and lethal in another; this works out which one you are in.
Compare with other animals
The same axes for every animal, side by side — the way the guides are written makes that a fair comparison rather than two articles.
Basslets, side by side
Same axes, same care guides — the honest way to choose between types.
See all Basslets side by side →
