Seeing a pregnant molly fish raises one central question: what if other fish will eat the fry? When I first faced this dilemma, I had a community tank with angelfish, guppies, plecos, and neon tetras. Luckily, I found the answer to this question throughout the years of growing these beautiful creatures.
Here is a table of seven common freshwater species and their relationship with molly fry:
|Fish Type||Will They Eat Molly Fry?|
As we move forward, I will elaborate on these different species and their relationship with molly fish fry. Then, I will share a few tips that may help you raise these delicate creatures in your main tank (even the newborns).
Also Read: Molly Fry 101
What Fish Will Eat Molly Fry?
This question matters because the wrong tankmates will eat all your babies before they can mature. It won’t do you any good to clean the tank and maintain the correct parameters when you have predators in the water.
If you’re trying to identify suitable tankmates for molly fish and their fry, avoid the following:
If this answer has confused you because you want to find a species that can live peacefully with adult mollies and their babies, you have already failed.
You can’t keep molly fry in the same aquatic space as their parents. Some fish care for their young. For instance, cichlids have a reputation for being violent.
And yet, a study by Jennifer L Snekser and Murray Itzkowitz, found in the National Library of Medicine, determined that convict cichlid parents that stayed with the same mate in a monogamous relationship were more likely to participate in the biparental care of offspring.
A paper in Current Biology came to the same conclusion. It identified cichlids that protected their children from predators.
Therefore, you can see why some aquarists would choose to raise molly fry in the same aquarium as their parents. Unlike cichlids, mollies are friendly and social.
Newcomers have every reason to leave their molly fry in the care of their parents. The decision sounds rational, but it is wrong.
If you leave a female molly in a nursery tank after it gives birth, the creature will eat the babies. You should separate molly fry from their parents.
Angelfish are a danger to molly fry. They will eat anything small enough to fit in their mouths. Admittedly, this applies to most fish. But angelfish stand out because of their aggressive tendencies.
Some people may describe them as semi-aggressive. Either way; you cannot trust them around smaller creatures. You can reduce their aggressive temperament by maintaining optimal conditions and providing sufficient food.
However, this species is problematic because of its unpredictability. They may attack, kill, and eat molly fry even when the tank has plenty of food.
Bettas would make poor neighbors for molly fry. They are highly aggressive and won’t hesitate to fight one another to the death. The females are friendlier, but that doesn’t make them suitable tankmates for molly fry.
A study carried out in the BSU aquatics lab blamed this aggression on factors like the number of rivals in the vicinity, the absence of female bettas, and more.
A research gate paper has identified aggression in Bettas as an indicator of pollution. In that regard, you could argue that bettas are more likely to eat molly fry in aquatic spaces under the wrong conditions.
However, bettas are called Siamese fighting fish for a reason. They can still manifest violent tendencies in well-maintained tanks. For that reason, you cannot trust them with your baby mollies. They will eat the fry.
Guppies will eat their children. Like mollies, they practice filial cannibalism all the time, which is why aquarists keep guppy parents and their offspring in different tanks. If guppies can eat their babies, why wouldn’t they snack on molly fry?
You should only pair baby mollies with adult guppies when you want to reduce the molly fry population. Otherwise, separate them before you lose your baby mollies.
5. Neon Tetras
No one expects neon tetras to appear on this list because they are peaceful creatures that can co-exist with other peaceful species. It wouldn’t be an exaggeration to call them sensitive.
If you notice signs of aggression like fin nipping, something has gone wrong. The neon tetras are stressed. Are they mating? Is the tank too small? Do they have food?
Various factors can generate stress in neon tetras, forcing the creatures to attack their neighbors. Stressed neon tetras are more likely to eat molly fry. However, that doesn’t make happy neon tetras safe.
Neon tetras in a clean, well-maintained tank are more than capable of eating molly fry. Don’t forget: the babies are small enough to fit in a neon tetra’s mouth.
That is enough to make neon tetras a threat. They will eat the baby mollies because they cannot differentiate the fry from any other snack. Don’t get complacent simply because neon tetras are known for being peaceful.
6. Dwarf Gouramis
Molly fry can survive in a tank with dwarf gouramis. However, you cannot guarantee positive results. Female dwarf gouramis can eat their eggs. Therefore, you cannot trust them to leave the molly fry alone.
Dwarf gouramis have one advantage. They are peaceful. If you have enough hiding places, the molly fry can survive.
But the size difference between dwarf gouramis and molly fry is still significant, and the baby mollies can fit in a dwarf gourami’s mouth.
You can’t expect dwarf gourami to ignore every baby molly it comes across. Like every fish, these creatures are opportunistic eaters.
Rainbowfish are safer than most of the species on this list. They are peaceful and friendly, especially if you keep them in groups. However, again, they are opportunistic eaters, just like every other fish.
You can’t trust them to ignore every tasty snack they encounter, even when that snack is a healthy molly fry. Rainbowfish can display aggressive tendencies only if you expose them to stressful stimuli.
For instance, is their tank overstocked? Rainbowfish hate crowded conditions and may lash out if their aquarium is too small. The diet is equally important.
Do they have enough food? Do you feed them on time? If the rainbowfish are fighting for meals with their neighbors, they may turn on the molly fry because the creatures are helpless.
Interestingly, you cannot fix overcrowded conditions by keeping the rainbowfish in small numbers. These creatures are happiest in groups of six or more.
The stress and anxiety will encourage the rainbowfish to attack their neighbors if they don’t have enough company. The creatures will target docile species that can’t fight back.
And unfortunately, fish don’t get any more docile and vulnerable than baby mollies. The solution to overcrowding in such situations is to get a bigger aquarium.
8. Other Fish
Listing the fish that will eat molly fry is endless. That is because almost any fish that can fit a fry in its mouth will gladly eat it.
For that reason, I typically recommend raising the fry in a nursery for about two months before introducing them to the main tank.
After two months, the molly fry enter their fingerling stage. At this point, they are roughly 4-6 inches in length, which is more than enough to live with adults.
While the fry are in a nursery, it is essential to introduce a proper filter, a heater, and some sort of aeration. Try maintaining a stable temperature of 75 to 80 degrees F.
Also Read: What Do You Do With Molly Fry?
Is There A Way To Raise Molly Fry With Adult Fish?
Creating a conducive nursery is the best choice. However, not everyone has the time or the means to start a brand new aquarium. Fortunately, you can raise the fry in community tanks by taking the proper steps.
- Before diving into it, it is worth mentioning that bottom dwellers like Plecos and Cory Catfish are not likely to harm molly fish fry. So, if your main tank features mainly those, you are probably okay.
But if you have mid or top dwellers, start by providing plenty of hiding spots. I would recommend dense foliage, especially floating plants with brushy roots that fry love getting behind.
Here are a few common examples:
- Amazon Frogbit (Limnobium laevigatum)
- Red Root Floater (Phyllanthus fluitans)
- Water Lettuce (Pistia stratiotes)
You should also keep your fish adequately fed. Starved fish will get more stressed and turn quickly to fish fry. Try not to skip any meals.
As for the fry, they require a different feeding schedule. They eat up to five times a day, depending on their age. They also eat different kinds of food at different ages:
|The Food Type||At What Age|
|Infusoria||Until day 7|
|Baby brine shrimp||Between days 7 and 21|
|Freeze-dried/frozen foods||Day 21 and beyond|
|Worms||From week 5 and beyond|
|Flakes/pellets||From week 8 and beyond|
Bear in mind that even after taking the proper measures, about half of your molly fry won’t survive. That is their general survival rate, and it goes even lower in community tanks.
Also Read: Will Molly Fry Survive In The Main Tank?
When a female molly fish gets pregnant, it is best to move her to a separate tank. Then, after she has done giving birth, she should return to the main tank. Otherwise, she’ll eat the fry.
Ideally, the fry should remain in the nursery for about two months. Then, you can safely move them back to the community tank.
If you can’t create a nursery, ensure there are enough hiding places in your main tank. If there aren’t, fish like angelfish, bettas, guppies, and adult mollies will quickly eat the fry.