Fathead minnows are small freshwater fish that are native to the North American continent and are found in waters from Minnesota down to Texas and as far east as New York.
They are members of the Pimephales genus of fish, which are also commonly known as killifish or pupfish by hobbyists who raise them in aquariums. They can be found in warm waters around the world, especially throughout the Southern United States and in Central America. Fathead minnows are generally brown with stripes, but they can come in a variety of colors and patterns depending on their surroundings and how they were bred by humans.
Fathead minnows fish, scientifically known as Pimephales promelas, are freshwater small fishes that belong to the Cyprinidae family. The name of the genus, Pimephales, is derived from the Greek word ‘pime’ which means ‘to drink’, and ‘phales’ which means ‘to possess.’
They are small, colorful fish that make great aquarium pets and are often sold as feeder fish for larger aquarium fish such as catfish, bass, walleye, and others. Because they are inexpensive and easy to breed in captivity, fathead minnows also make great pets to start with when learning how to care for fish in an aquarium.
Origin and descriptions
Fathead minnows are native to the midwestern United States and the Great Lakes region of Canada, but they are also popular in aquaculture in many countries around the world because of their hardiness and fast growth rate, although they are often kept only in outdoor tanks or ponds due to their short lifespan and intolerance of low temperatures.
Fathead Minnows (Pimephales promelas) are found naturally in small lakes and slow-moving rivers and creeks, typically in sand or silt substrates. Their natural diet includes small insects and worms. They prefer water temperatures of 68–75 degrees Fahrenheit. In some cases, they will survive in warmer waters, but their growth rate may be slower than that of other minnow species.
Raising fathead minnows for bait is a popular pastime for anglers who enjoy catching bluegill or other panfish. Raising a batch of mini-minnows from eggs to adulthood is also fun for kids and adults alike.
The fathead minnow is a species of freshwater fish in the genus Pimephales. It is very common in many lakes and streams and may be an important forage base for larger predator species, including juvenile salmonids. It has been introduced in Western Australia to enhance sport fishing opportunities.
The native range of fathead minnow includes most of North America, east of the rocky mountains from southern Canada to northern Mexico, plus Bermuda and Puerto Rico. Like other members of its family, it possesses two dorsal fins with sharp spines, two pelvic fins located just behind its pectoral fins, and no lateral line (the groove running along each side).
They have rounded bodies covered with small scales which give them a fat appearance; hence their name. They also have broad, terminal mouths with both upper and lower jaws that jut out, allowing them to consume prey items at all levels in deep water.
Fathead minnow scientific name
The scientific name of the fathead minnows fish is Pimephales promelas
Fathead minnow habitat
Fathead minnows can live in a variety of freshwater habitats, including small streams, ponds, and lakes. If a population becomes too crowded, they may also inhabit nearby brackish water or saltwater environments to reduce competition for resources.
Fathead minnows can also live in garden ponds that contain non-native species; these are sometimes called hitchhiker fish because they have outcompeted other species for food sources and habitat.
Fathead minnow size
Fathead minnows fish only grow to about 2.6-4.0 inches (7-10 cm) in length.
Due to their small sizes, the minimum recommended tank size is 10 gallons.
Minnow tanks should be between 10 and 20 gallons in size, with a good filter and aeration, and they also need a place to hide from larger tankmates. This can be accomplished by using plants or rocks placed near their favorite hiding places to provide them with adequate cover. Do not overstock your tank with minnows, as they need space to hunt for food.
The pH of the water should range between 6.0 and 8.0; higher levels encourage algae growth, while lower levels tend to hurt live plants. Minnows do best at temperatures between 70 degrees Fahrenheit and 80 degrees Fahrenheit. Water hardness should be kept within specific parameters: 10–30 dH (diatom hardness) is ideal, but minnows can withstand much higher levels (as high as 50 dH).
A temperature change of 5 degrees is enough to kill some species of minnows; therefore, it is important that you monitor both temperature and humidity when keeping fish indoors.
Take care to avoid ammonia build-up and nitrite spikes, which will eventually cause irreparable damage to your living environment. Beware that a fluctuation of more than 4 ppm may prove fatal.
Only keep fathead minnows with other peaceful species. Goldfish, for example, make great tank mates for these livebearers. You can also house them with small, peaceful livebearers like mollies, guppies, and platys. Do not put them in a tank with aggressive fish like tiger barbs, as they’ll eat your little guys!
Fatheads also get along especially well with danios and shubunkins.
Fathead minnow breeding in aquarium
In late summer, fathead minnows begin spawning at water temperatures near 18°C (64°F) and continue to do so until they drop below that temperature. Each female can spawn 16 to 26 times per year and produce 6,800 to 10,600 eggs annually through fractional spawning. These breeding sites are defended by males, who establish territories under submerged objects.
They lay eggs on the underside of hard surfaces in the water attracted to males. In addition to pallets, plastic tarps, boards, and irrigation tubing, farmers use various substrates to spawn. From the time the eggs are laid, until the eggs hatch, the male defends the nest. Spawning is triggered by temperatures higher than 64 degrees F.
Females spawn multiple times a week, even more frequently than this. Spawning stops when the water reaches 84F or higher. Minnow eggs measure about 1.25 to 1.65 millimeters.
Juveniles grow rapidly, reaching 45–50 mm in 90 days, and most fathead minnows die before reaching two years of age after spawning.
Are they aggressive or peaceful?
Fathead minnows fish are actually quite peaceful. You can use them in schools and they’ll get along with other members of their species and many other types of community fish.
The bottom line is you don’t have to worry about putting two male or two female fatheads together; they’re equally as docile with one another, making them great choices for community tanks.
Fathead minnow care
Fathead minnows prefer a water temperature between 65-75 degrees F. The ideal pH for them is about 7, but they can survive in a range from 6.0 to 8.5. They require at least 1% of oxygenated water per inch of length, so if you’re stocking ten-inch long minnows, you’ll need 10% of surface area at minimum to meet their oxygen needs.
Some owners also report that aeration helps these swimmers stay active and healthy. Keep in mind that these are schooling fish, and should be kept with other fatheads; you may have difficulty maintaining populations with fewer than 20 fatheads per gallon of water. We recommend a tank size of at least 20 gallons per pair. Keep your minnows well fed!
What do minnows eat?
Fathead minnows are omnivores, meaning they will eat both plant and animal matter. They feed on zooplankton, aquatic insect larvae, snails, and tiny bits of organic matter floating in the water. Just like most other members of their family, they also feed on microscopic algae found inside certain species of plants (like moss).
Overall, though, fatheads primarily dine on small invertebrates. Aquatic worms, for example, are commonly eaten by these little guys. After all is said and done, over 80% of a fathead’s diet comes from animals.
Fathead minnow lifespan
Fathead Minnows can live for a maximum of 2 years in a tank that has ample oxygen and filtration.
Parasites and diseases
As one of many health problems that can harm freshwater fish, external parasites and diseases may attack fathead minnows. The most common disease of these bottom-dwelling freshwater animals is ich. Ich, or ick as it is sometimes called, is caused by a parasite called ichthyophthirius multifiliis.
It causes small white spots to appear on fathead minnow bodies and fins, giving them a salt-and-pepper appearance. Ich also depletes an infected fish’s red blood cells and may lead to death if left untreated. If your fathead minnows exhibit any symptoms, such as increased lethargy, jumping out of the water, unusual spasms, or clamped fins, take immediate action.
Do they make good pets?
Despite their appearance, fathead minnows make great pets. They’re fun and easy to care for and relatively affordable. They eat live food such as bloodworms, brine shrimp, or small insects (similar to crickets). This can easily be purchased at a pet store. Just be careful not to feed them too much or too little; they don’t do well if they are overfed or underfed.