Silver Moony (Mono Fish)

Monodactylus argenteus

The Silver Moony or Mono Fish (*Monodactylus argenteus*) is one of the most iconic and dynamic estuarine fish available on the market. Characterized by a very particular discoidal body, extremely compressed and diamond-shaped (or kite-shaped), it sports a dazzling pure silver livery that reflects light like a mirror. Juveniles have two marked vertical black bars across the eye and the operculum, and a flashy bright yellow dorsal fin. Reaching 25 cm (10 inches) in height and length, it is a lightning-fast and tireless pelagic swimmer. Its immense difficulty of keeping lies in the fact that, although it is often sold (and survives as a juvenile) in fresh water, the adult is strictly a heavy brackish or marine fish, and will die prematurely in normal domestic aquariums.

Family: Monodactylidae
Origin: Indo-Pacifico (Estuari, mangrovie e zone costiere dall'Africa orientale all'Australia e Sud-est asiatico)
Tank use: Used in 0 tanks

Temperature

24 °C - 28 °C

7.5 - 8.5

Water type

Brackish

Tank level

Zona media e superiore. Pattugliano l'intera vasca in branco ad altissima velocità.

Adult size

25 cm

Description

Surface Explosion:

Feeding a school of healthy adult Monos is an adrenaline-pumping experience. They do not eat, they attack. As soon as you throw the flake food or shrimp on the surface of the water, the silver school will dart vertically at frightening speed breaking the surface with a roar and splashing water out of the tank just to snatch the food from each other's mouths.

Care and observations

The Condemnation of Fresh Water:

In stores you find them swimming happily in classic freshwater aquariums, as big as a coin, and they often tell you that "they live in tap water". It is a fatal half-truth. In nature, they are born in the ocean and the puppies swim up the fresh rivers to take refuge from predators. But as they grow, their biological clock forces them to return to the sea. If you do not buy bags of real synthetic Marine Salt (not table salt) to gradually transform your aquarium from fresh to "brackish" (or totally marine) as the months go by, the adult will wither, lose its colors and its kidneys will block.

25 Centimeter Silver Porcupine:

Do not be fooled by their tender puppy dimensions. An adult school (they absolutely must be at least 6) will become huge: big and 25-centimeter (10-inch) tall fish, shaped like a silver serving platter. They cannot in any way be kept in aquariums less than a meter and a half (5 feet) long, otherwise they will smash their snouts on the glass in panic.

Goodbye to Live Plants:

Prepare for a "bare" sea-type aquarium. First of all, the salt will kill normal aquarium plants. Secondly, the *Mono argenteus* is an "aquatic goat": it loves vegetables. Any soft leaf you try to insert (even the expensive Anubias), will be devoured by the school within 48 hours.

Fish profile

Temperament: Estremamente vivace, frenetico e gregario. Moderatamente gerarchico all'interno del proprio branco (si rincorrono costantemente), ma pacifico verso altre specie di taglia adeguata.
Diet: Onnivoro Vorace (tendenza erbivora). Estremamente golosi. Divoreranno istantaneamente qualsiasi mangime, ma esigono un massiccio apporto vegetale per evitare costipazione: alghe nori, spirulina in fiocchi, lattuga sbollentata e piselli. Integrano con chironomus e artemia salina.
Tank level: Zona media e superiore. Pattugliano l'intera vasca in branco ad altissima velocità.
Minimum group: 6
Adult size: 25 cm
Minimum tank: 400 L
GH: 15 dGH - 30 dGH
KH: n/a
TDS: n/a
Conductivity: n/a
Sex ratio: Grande banco obbligatorio (minimo 6 esemplari). In numeri inferiori o da soli diventano apatici, letargici e preda di un nervosismo estremo che li porterà a schiantarsi contro i vetri per la paura. Sessi indistinguibili visivamente.
Feeding frequency: 1-2 volte al giorno. Mangiano in superficie con voracità esplosiva, spruzzando acqua fuori dalla vasca.
Bioload: Alto (Grandi dimensioni, metabolismo veloce e massiccia assunzione di cibo)
Flow: Corrente Molto Forte. Sono pesci di barriera e marea, amano flussi ultra-ossigenati creati da grandi pompe di movimento marine (wavemakers).
Jump risk: Covered tank required
Reproduction: Inesistente e non documentata in acquari domestici. In natura depongono le uova pelagiche nelle acque costiere marine o salmastre; gli avannotti risalgono poi la corrente nei fiumi d'acqua dolce per crescere (ciclo catadromo/anfidromo parziale). Tutti gli esemplari sono pescati in natura.
Compatibility: NON INSERIRE IN ACQUARI DI COMUNITÀ STANDARD. Ucciderebbero le piante e mangerebbero i pesci piccoli (Neon). Mantenimento esclusivo in vasche dedicate alle mangrovie (Salmastre) con compagni che tollerano forte salinità e il loro nuoto isterico: Pesci scatola d'estuario (Scatophagus argus), Toxotes jaculatrix (Pesce Arciere), pesci palla verdi (T. nigroviridis) e murene d'acqua salmastra.

Image gallery

Licensed images linked to the species or, when marked, to the closest representative taxon.