Zodiac Loach
Mesonoemacheilus triangularis
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Overview
Synonyms | Nemacheilus triangularis, Noemacheilus triangularis, N. triangularis tambraparniensis |
Distribution | India |
Maximum Size | 7.5cm (3") |
Temperature | 20-26°C |
Water Parameters | pH: 6.5-7.5, dH: up to 15 degrees. High O2 level essential. |
Compatibility | Specialist community |
Lighting | No special requirements |
Sexual Dimorphism | Male fish possess a suborbital flap, and mature females will be fuller bodied. |
Feeding | Catfish pellets, granules, flake and frozen foods |
Description
Care
The Zodiac Loach is known from the river systems either side of the Western Ghats in Kerala and Tamil Nadu states. Here, they are found in clear, cool, swiftly-flowing hillstreams over pebbly substrates. These pretty, torpedo shaped loaches are members of a group of bottom dwellers referred to as Brook Loaches, and they occupy a similar, but not quite so harsh niche to that of the balitorids (Hillstream Loaches). Nemacheilidae is a huge and diverse family, currently containing over 450 species and is comprised of many popular genera, including Aborichthys, Acanthocobitis, Mesonoemacheilus, Nemacheilus, Schistura, and Yunnanilus. A requisite for their care is highly oxygenated water with plenty of current, and tight fitting coverslides are a must. The Zodiac Loach can be a little territorial with conspecifics, and should be kept in spacious aquaria with plenty of visual barriers amongst the decor. Their antagonistic behaviour is not so much of an issue in the wild, where fish can easily move from one territory to another, but it can certainly present problems within the confines of the aquarium. Provide a sandy substrate along with plenty of nooks and crannies formed from pebbles, rocks, pieces of slate, and tangles of driftwood - ensuring that lines of sight are broken up. Plants are not found in any great abundance in the fast-flowing waters of the natural habitat of the Zodiac Loach, so are not considered essential; however, robust species such as Anubias and Microsorum tied onto driftwood will help with water quality and will make the aquarium look more aesthetically pleasing, as well as creating more hiding places. The best way to keep these loaches is either singly, as a known compatible pair, or in dense groups (10+). Larger groups mean that any territorial aggression is spread amongst the shoal, so that no one fish bears the continual brunt of any sporadic antagonistic behaviour. Zodiac Loaches do not usually show aggression towards other current-loving fish, providing that they are not other nemacheilids. Nonetheless, tiny placid tankmates are best avoided, as are species with long fins. Good companions could include some of the smaller Barbs, Barilius/Opsarius, temperate Bitterlings, Crossocheilus, Danios, Devarios, or Garras, and shoals of these will act as 'dither fish', encouraging the loaches out into the open. Like other species that inhabit fresh running waters, these loaches will not tolerate a build-up of nitrates within the aquarium and require excellent water conditions at all times if they are to thrive - so powerful filtration and regular partial water changes are essential. May also be seen on sale as the Batik Loach.
Feeding
Small frozen foods such as bloodworm, white mosquito larvae, vitamin-enriched brineshrimp, and daphnia. Will also take sinking catfish pellets/tablets/granules.
Breeding
This species has been bred in the home aquarium, and there is but a single breeding report. A well-conditioned pair were acclimatised to a separate (filtered) breeding tank that was furnished with spawning mops weighted down onto the glass base, and the water temperature set to 24 °C. The following day, the fish were observed swimming up and down the side of the tank together, and then seen to be entering one of the spawning mops. Closer examination revealed hundreds of eggs on the base of the tank, which the adults were feasting upon. The adults were acclimatised back to the main aquarium, and just 24 hours later, the eggs began to hatch (at this point the filtration was switched to a gentler air driven filter). Once the fry, which numbered around 500, had absorbed their yolk sacs, they were offered infusoria and powdered fry foods, before moving on to baby brineshrimp (Artemia nauplii).
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