Poecilia sphenops
Poecilia sphenops inhabit bodies of water in South and North America. Very often the fish can be found in watersheds where rivers flow into the ocean. The yellow-black mollinsia is a product of breeding, with the black and gold mollinsia serving as source material.
Poecilia sphenops has an attractive bright yellow body colour with dark spots. Males are slightly smaller than females, their length does not exceed 12 cm. Males are slender and have a gonopodium, a rod-shaped anal fin. In addition, males have an elongated dorsal plumage, while females have a rounded shape.
The yellow-black mollinsia is a peaceful and fast fish. They require an aquarium with a capacity of about 80 liters per pair. Fish can contain pairs, but still feel more comfortable fish in a flock dominated by females. To contain 6-8 fish need an aquarium of 250 liters. possible content in a common aquarium with other peace-loving fish, such as pecilians, tetras, rainbow fish.
The perimeter of the aquarium should be planted. A few bushes of floating plants should preferably be placed on the water surface. Need to take care of free space for swimming fish.
Water parameters: temperature 22-28º C, hardness dH 8-25º, pH 7,0-8,5. Pisces are sensitive to sharp fluctuations in water temperature, so when changing water, fill the water at the same temperature as in the aquarium. Aeration, filtration and a weekly change of 1/3 of the aquarium water to fresh water is essential. Due to the fact that in nature mollinesias live in brackish water, it is advisable to dissolve table salt in the aquarium water in the proportion 1 tbsp salt per 80 liters of water.
The lighting should be bright. The fish are very beneficial to sunlight, so if possible, let sunlight into the aquarium, but do not overdo it, as bright light can lead to the rapid development of green algae, which can significantly spoil the appearance of plant leaves and decoration.
The fish diet consists of a variety of dry and live food. Preference should preferably be given to live food: Artemia nauplii, daphnia, chaff. Plant food in the form of shredded lettuce and spinach leaves, cucumber and courgette slices is required. Feed the fish twice a day without overfeeding. It is important to give the fish a day of rest once a week, which has a positive effect on their well-being.
Reproduction
The Poecilia sphenops is a viviparous fish. Females reach sexual maturity at the age of six months, and males at one year.
If the keeping conditions are fully satisfactory for the fish, they spawn almost continuously in the aquarium. The male fertilizes the female with his gonopodium, which has a sperm tube inside. After fertilization, the female carries the fry for 1-1.5 months. A sign that the female will soon give birth to fry is a dark spot near the anus and a strongly rounded abdomen. The female begins to look for a hiding place in the aquarium. As soon as such behavior will be noticed, it is desirable to put the female in another small aquarium, densely planted.
The female usually spawns in the morning hours. Depending on the physiological condition of the female, she is able to spawn sometimes about a hundred fry. The fry are large and immediately after birth they lie motionless on the leaves of plants and the ground. Immediately after birth, the female should be removed.
The fry are fed with Artemia and dry food intended for fish fry 3-4 times per day.
The Poecilia sphenops has a life span of about 3-4 years.
