A quick search on the internet can usually tell you whether your fish species spawn or lay eggs. This tells you to watch for a bulging belly from pregnancy, or little jelly ball-like eggs in your tank. If you are expecting chicks, try to find out as much as you can about your fish species, as caring for chicks can be very difficult.
Step
Method 1 of 3: Identifying Pregnancy and Birth
Step 1. Use this method for spawning species
Guppies, mollies, swordtails, and platies are probably the most common species of spawning fish. Male and female fish of this species fertilize, then eggs are formed inside the female's body. After about a month or two (for most fish species in the aquarium), the eggs will hatch into fish, and then be born by the mother.
Search the internet for your fish species to see if it lays eggs (oviparous) or gives birth (viviparous)
Step 2. Identify the male and female fish
Generally, males of this species give birth to a brighter and more complex coloration, and have a small and long anal fin on the underside near the tail. The color of the female fish tends to be paler with an anal fin that is triangular or fan-like. If you can identify the sex of the fish, it will be easier for you to tell if the fish are fighting (usually two males or two females) or breeding or preparing to breed (one male and one female).
In some species the sexes are more difficult to distinguish so you may need the help of an expert from a fish shop
Step 3. Watch for any breeding activity
Each fish species behaves very differently when spawning or when engaging in other breeding activities. In most fish species, including gourami, the male chases the female fish vigorously, sometimes to the point of scratching, biting or causing other injuries. In some other fish species, such as discus, male and female fish will work together to protect one part of the aquarium from other fish. In both cases, when fertilization occurs, the male and female fish sometimes grab onto each other, somersault, wriggle around each other, or perform activities that are subtle and difficult to observe.
Step 4. Check for any bulges that indicate pregnancy
In female fish will grow a bulge behind the stomach. The female abdomen generally enlarges within 20-40 days, either enlarged and rounded or squared.
- Some species, such as the balloon molly fish, have a natural protrusion towards the front, just below the gills.
- In fat male fish can grow a lump in front of the chest. If you don't feed the fish for two or three days, the lump due to obesity will shrink, while the pregnancy lump of the female fish will become more pronounced.
Step 5. Look for red or black spots
Pregnant female fish usually have gravid spots on the abdomen near the vent. These spots are usually black or bright red in color and become more pronounced as the pregnancy progresses.
Some fish always have these spots, but they will generally become lighter or darker when the fish is pregnant
Step 6. Decide how you will treat the fry
Taking care of the fry can be really challenging, and generally requires a separate aquarium to keep the adult fish or a water filter from endangering the life of the fry. If you're not ready to do this, try contacting a fish shop or experienced fish enthusiast who may be able to help you or get the fish from you. If you decide to take care of fish fry, you can start from the steps below regarding raising fry, besides researching your fish species specifically is also highly recommended.
Method 2 of 3: Recognizing Nesting and Egg Laying
Step 1. Use this method for spawning fish species
Many aquarium fish are egg-laying species, including discus, betta, and most gourami. The female of this species lays hundreds of eggs, usually in a prepared nest area at the bottom of the tank, the walls, or the surface of the water. If there are male fish in the same aquarium, the male fish will either fertilize after the eggs are released or when breeding with the female fish before, depending on the fish species. The eggs will later hatch into live fish.
- Search the internet for your fish species to see if it lay eggs (oviparous) or give birth (viviparous).
- Females of some species can store sperm for several months before using it for fertilization, so new aquariums containing only females can sometimes reproduce.
Step 2. Watch for signs of fish making a nest
Some types of fish that lay eggs create nesting areas to keep their eggs safe. Fish nests can look like small holes or mounds of gravel, but fish nests are not always visible. Some types of gourami can build more elaborate nests than bubble blobs, usually made by male fish along the surface of the water.
Step 3. Check for eggs
Some females bulge as the eggs develop inside them, but usually there are no major changes and they don't last long. Once removed, these eggs will look like little jelly balls. These eggs are usually dispersed in the water, but in some species, the eggs are in nest mounds or attached to the bottom or walls of the aquarium.
Many species of fish that lay eggs have special activities when breeding, including carp. This activity is usually seen to be done with a lot of excitement and can last up to several hours, ending with the storage of the eggs
Step 4. Prepare for hatching eggs
Caring for a fry can be very difficult, but when you don't realize it, you still have some time before the eggs hatch. Consult a fish shop if you are interested in caring for your own fry, as the process varies by species. If you don't know it, look at the steps for raising chicks for a basic guide, but don't assume the steps will work perfectly for every species of fish.
Method 3 of 3: Raising Fish Calves
Step 1. Learn your fish species as best you can
The instructions below can teach you the basics and are useful as an emergency measure if your tank suddenly fills up with chicks. However, taking care of fry or fry is a challenge and the more you know the nature of a particular species of fish the better.
- For more details on your particular species of fish, follow these instructions for breeding and raising guppies and betta fish.
- Ask a fish shop employee or fish fan for directions online. This is usually more helpful than advice given from general pet stores.
Step 2. Replace the filter with a sponge filter
If you have a water filter that sucks in water or creates a water current, turn it off and replace it with a sponge filter from a fish shop. Otherwise, the water current from the filter can weaken the fry or even suck the fry into the filter and kill them.
Step 3. Separate the fish
Many fish breeders set up a new aquarium and move fish eggs or chicks into it. However, if you are not an experienced fish keeper, it will be difficult to create a safe and stable environment in a short period of time. Instead, you can use a plastic separator net from the fish shop to separate the fish. Depending on the species, the broodfish may nurse or prey on the fry, so look online for clues that match your fish. If this is not possible, decide how to separate them based on the nature of the parent:
- If the brood is laying eggs in the nest and guarding it from other fish, use a net to separate the brood and eggs on one side and the other fish on the other.
- If the mother fish gives birth or sprays eggs in the water, place all adult fish to one side. The fry should be able to swim through the net to escape from the adults.
Step 4. Give special feed for fish fry
Sometimes you can buy special feed for chicks from a fish shop, but you will need to choose from a variety of other options. Infusoria, liquid fish food, or rotifers are usually safe to use. However, as they grow, the fish will need additional food which can vary depending on the fish species and size. Ask the fish shop clerk for directions based on your fish species.
If you can't get to the fish shop, feed the chicks a hard-boiled egg yolk strained with cheesecloth
Step 5. Plan how to care for the puppies as adults
Set up an additional tank early if you plan to treat some fish. Instead, contact fish shops and fish enthusiasts in your area to sell or give away your chicks once they reach a certain age.
Tips
If you don't want your pet fish to reproduce, separate the male fish from the female. If it's too late, contact a fish shop that can pick up the fry
Warning
- If your pet fish is fat, slow, and looks stiff or sharp, ask a specialist or your local fish shop. It's possible that this is a disease, not pregnancy.
- Unless you have provided the right environment and care, the majority or even all of the fry will die.
- Never release fish into natural water, unless you have previously taken fish from the same water source because it can cause the number of fish to increase to too much which can actually damage the environment.
