A stunning fish with a fiery personality, Manonichthys splendens may look tempting but they could cause problems in your reef tank.
At first glance, it is easy to fall in love with the splendid dottyback (Manonichthys splendens). Its dark base colour is overlaid with bright yellow rows of spots that merge into a striped pattern. Blue edging on the dorsal and anal fins, along with a dark eye band, completes this incredibly eye-catching fish.
However, if you’re lucky enough to encounter one in your local marine store, it’s worth pausing before making a purchase. Beneath that beauty lies a highly territorial fish with a surprisingly aggressive temperament.
Temperament and Compatibility
Dottybacks as a group have a reputation for being a fiery bunch. Even the species that are far smaller than the splendid dottyback have the potential to terrorise tank mates.
This species should not be trusted with any shy, peaceful species, like small gobies, that won't be able to hold their own. Suitable companions need to be robust and similarly aggressive. Some damselfish, larger wrasses, tangs and angelfish can work as tank mates if the tank is large enough. However, large predatory fish also need to be avoided as they may see the dottyback, especially while juvenile, as food.
This aggression is not just shown to other fish; shrimps and other crustaceans are likely to become a target too. Corals and other sessile invertebrates are generally safe, however, which is why this species is often labelled as "reef safe with caution". Indeed, coral structures provide valuable shelter, allowing the fish to retreat into intricate networks of hiding places for extended periods.
Related article: Back to saltwater: starting simple with beginner corals.
Tank Size and Setup
Reaching a potential size of 13cm (5.1"), splendid dottybacks can grow to double the size of the commonly encountered orchid dottyback (Pseudochromis fridmani). So, it stands to reason that they will need far larger aquariums.
A tank measuring 90x45x45cm (36x18x18") will work, holding roughly 180 litres (40 UK gal/47 US gal) of saltwater. Decorate the tank with plenty of rock, creating nooks and overhangs for the dottyback to explore. The more hiding spaces the better, and spread them right across the length of the tank. This may allow tank mates to occupy some of these spaces.
Related article: Marine Hitchhikers: Natural Pest Control for Reef Tanks.
Water Parameters
The splendid dottyback is a true reef dweller, so water chemistry is unlikely to be a problem. Sticking with the standard reef parameters below will work well for this species.
- Salinity: 32-35ppt
- Specific gravity: 1.023-1.026
- pH: 8.1 - 8.4
- Temperature: 23-27°C (73-81°F)
Splendid Dottyback Fact File
Scientific name: Manonichthys splendens
Size: up to 13cm (5.1”)
Origin: Indo Pacific, from Philippines and Indonesia to Australia.
Habitat: Typically associates with areas of corals and sponges in drop-offs and seaward reefs down to depths of 40m (130'). Usually found alone, but occasionally pairs can be seen close together on the reefs.
Tank size: 90x45x45cm (36x18x18").
Temperament: Can be shy and secretive, hiding out in holes and crevices amongst the rock work. However, this fish will aggressively defend its territory. They may eat small crustaceans but will generally leave sessile invertebrates alone.
Feeding: Generally unfussy, eating most live, frozen and dry foods but they'll supplement this with naturally occurring invertebrates found amongst the live rock. Feed a couple times a day with a varied diet.
Availability & cost: Rare to find, prices vary greatly but expect to pay upwards of £50.
Related article: Marine starter fish to avoid.
Is The Splendid Dottyback Right For You?
So, while this is a stunning marine fish, the restrictions they place on potential tank mates make them a difficult species to house in most reefs. Splendid dottybacks are best suited to being the stunning centrepiece for which the aquarium is designed around, rather than an addition to an existing community reef.