Moenkhausia costae
Moenkhausia costae naturally lives in shallow waters in the densely aquatically vegetated rivers Rio San Francisco and Rio Itapikuru and their tributaries, South Brazil. The fish have not been supplied to the domestic market, but it is now possible to get supplies from German aquarists who have succeeded in breeding the fish on an industrial scale.
Moenkhausia costae has a silvery body with a greenish sheen, which in the reflected light takes on a greenish-olive coloration. From the eye to the root of the tail plumage runs a thin line of golden coloration. A black stripe runs from the upper tail blade to the anal fin. The fins are transparent. Females are slightly larger than males and have a rounded abdomen. They also have a curved anal fin, while males have an almost straight anal fin. The maximum size of the fish is 6 cm.
Moenkhausia costae is an active, gregarious fish. Keep the fish in a group of at least 6. An aquarium of 120 liters is required for this number of fish. The aquarium should be densely planted and have a dark substrate, against which the coloration of fish will be particularly attractive. These hardy fish can adapt to different aquarium conditions. The fish spend most of their time in the lower and middle layers of the water.
The Moenkausia costa may be kept in a common aquarium with other peace-loving fish species. Need to pick up their neighbours in the neighborhood of fast fish, as shy and slow-swimming fish can be targets for harassment.
Water parameters: temperature 24-28° C, hardness dH 5-17°, pH 6,5-7,2. Requires filtration, aeration and weekly replacement of 1/3 of the aquarium water with fresh. The aquarium must be covered, otherwise at one point you will find all the fish on the floor.
There are no particular requirements for lighting, so focus on the light requirements of the plants growing in the aquarium.
The diet of the fish consists of a variety of live and frozen foodstuffs: daphnii, nauplii artemia and chironomid moths. The fish also happily eat flake food. The food is given twice a day. It should be noted that often, during the feeding of fish, between the dominant male and the other fish there are conflicts, which, however, never end in serious injuries.
Reproduction
For breeding Moenkhausia costae requires a spawning aquarium with a capacity of 25 liters. The fish do not spawn in a communal tank.
The spawning tank should be the following water parameters: temperature about 27° C, hardness dH 1-2°, pH 6.1-6.4. At the bottom of the separator mesh is placed on top of which fasten Ceylon fern bush.
Spawning stimulated daily replacement of ½ of the aquarium water with fresh. Spawning usually takes place in the evening. The female lays up to 200 yellowish eggs. Immediately after spawning, producers are removed, and the spawning tank darkened for a couple of days.
Hatched larvae begin to swim on the fifth day of life. They are very small, so the first 2-5 days of life they are fed infusoria-tuffle. Later, the fry are given artemia nauplii. The food is given 4 times a day. The fry grow quite rapidly.
Life expectancy for Moenkhausia costae under aquarium conditions is about 5 years.