Why Do Kribensis Eat Their Babies? (And How To Stop Them)

Normally, Kribensis will not eat their babies, they are generally fantastic parents. However, there can be factors that cause the parents to eat their fry. These include an unexpected disturbance in the tank, the presents of a predictor fish, or lack of food to raise the fry.

Kribensis were the first Cichlid I ever bred. I bought a pair of Kribensis about 20 years ago and kept them in a 29-gallon aquarium. I was astonished at how easy they were to breed. These bright, charismatic fish fit well into almost any community aquarium.

Kribensis are one of the easiest members of the Cichlid family to breed. Get yourself a pair, set the aquarium up correctly and they will spawn. Kribensis are excellent parents who protect their babies.

How Do Kribensis Look After Their Babies?

Normally, Kribensis are excellent parents. This is one of the many qualities that make Kribensis so popular. The male and female will pair up and form a strong bond. Often they form a bond that will last for life.

The two fish will choose themselves a cave, usually taking advantage of a decoration or feature in the aquarium, and spawn. They will produce hundreds of eggs. Once those eggs hatch, the parents will guard the young fry.

Over the years I have tried numerous different caves to spawn my Kribensis in, but recently I came across these on Amazon.

Once the fry become free swimming, the parents will shepherd them around the aquarium, warding off any other fish that stray too close to the young Kribensis. This is very often the first time the aquarists know their Kribensis have spawned.

What Causes Kribensis To Eat Their Babies?

In nature, there is a phenomenon whereby the parents decide conditions aren’t favorable to raise the fry, or they feel the fry are about to be eaten by a predator, and rather than just losing those fry, the best thing to do is eat the fry themselves, gain the protein and goodness from the fry as ‘food’, and then spawn again when conditions are more favorable.

They effectively ‘recycle’ the nutrients from the fry rather than lose them to a predator.

In our aquariums, conditions are different from those in nature. There are rarely set-ups whereby we keep Kribensis with a hardcore predator that might eat them. However, there are factors that can affect your Kribensis that they wouldn’t come across in nature. Some of these include;

Poor water conditions

In nature, water parameters generally stay stable. They don’t fluctuate. In or aquariums, however, what parameters, including temperature, can change in a very short space of time.

If a heater fails, and the temperature either drops or rises when the heater sticks ‘on’, the Kribensis parents may decide to eat their fry. Fry growth rates do vary by temperature.

Nitrates in the water are another factor that can cause Kribensis to eat their babies. Nitrates are caused when our fish go to the bathroom. Their poop is high in ammonia, which our filters convert to nitrite, and then to nitrates. Nitrates can essentially only be removed by changing some water. When the nitrates get too high, it can affect the Kribensis health and would certainly have an effect on the babies’ growth rates.

To prevent your Kribensis from eating their babies due to poor water conditions, monitor the water quality on a regular basis using a water test kit like the API Master Test Kit (check current price HERE). If you notice conditions are deteriorating, take evasive action.

External factors

One of the major external factors which cause our Kribensis to eat their fry, is being continually disturbed by the aquarist. If we keep poking around in the aquarium or banging on the glass, the fish may become ‘spooked’ and eat their fry.

To stop your Kribensis from eating their fry because of external factors, just leave them alone! That is hard, especially when you get your first spawn. However, if you leave your Kribensis alone for two or three weeks, the fry will grow rapidly and the chances the parents will eat them drops.

Ready to spawn again

Another factor that causes Kribensis to eat their own babies is when one or both fish are ready to spawn again. Kribensis will spawn on a regular basis, but occasionally, they get their timings wrong. Their instincts should tell them don’t spawn again until these fry are old enough to survive alone, but sometimes they will eat their own fry, just so they can breed again.

There is very little you can do when your Kribensis decide to eat their fry so they can spawn again. The only action is to remove the fry and raise them in a separate aquarium. This however means a lot of work for the aquarist. Not only do you now have two aquariums, but you also have tiny fry to take care of. Tiny fry that may need feeding five or six times a day.

Poor Genetics

In nature, only those fish who have strong maternal instincts will end up producing fry. Hopefully, those fry will inherit their parents’ maternal instincts. In our aquarium hobby, we generally want fish as cheaply as possible. This desire has led to fish being mass-produced at large fish farms.

At fish farms, the parents will spawn, then the eggs or fry are removed from the parents, a) because the survival rates of the fry go up when a dedicated fish farmer is looking after every single baby, making sure they survive to a saleable size and b) without baby fish slowing them down, the parents will want to respawn, producing more babies per pair of fish every year.

By removing the fry from the parents, the fry will survive no matter how good or bad the parents’ maternal skills are. This means in our aquariums, unlike in nature, even those fish with very low maternal instincts still get to successfully produce fry. We now end up with a large number of fish whose parents, and possibly grandparents had no maternal skills.

Sometimes, Kribensis parents need to ‘learn’ how to raise their fry. By leaving the fry with the parents, even though the first 3, 4, or 5 spawns may get eaten, the Kribensis will usually turn round and think ‘maybe, instead of eating all these babies, we should try raising them’.

Once the fish understand raising the fry is better than eating them, they will usually become good parents.

Can You Remove Kribensis Babies To Raise Them?

Yes, it is possible to remove the eggs or fry from the parents and raise them separately, although you should be aware it is a lot of work.

When you first notice your Kribensis have spawned, remove either the eggs or fry and place them into a dedicated aquarium. Within reason, the smaller the aquarium the better.

Putting a bunch of tiny fry into a 55-gallon aquarium doesn’t make sense. The fish will burn so much energy swimming around a huge tank. A 10 gallon might be a better choice. Feeding your fry good quality, small live or frozen foods will help your baby fish grow rapidly.

One thing to bear in mind if you are raising the fry is, what do you plan to do with 60 or 70 Kribensis when they have grown?

In Conclusion

Generally, Kribensis are fantastic parents. They will spawn and then raise their fry up to a point where they can fend for themselves. Occasionally, something goes wrong in the process and the Kribensis will eat their fry. They may eat spawn after spawn until the aquarist is ready to give up. If we can work out why the Kribensis are eating their babies, we can hopefully make a change that will stop them.

Raising baby fish is one of the best parts of the aquarium hobby. It is incredibly satisfying. If you don’t succeed at first, keep trying. The effort will be worth it in the end.

Article Sources

• tfhmagazine.com/articles/freshwater/keeping-kribs-the-culture-of-pelvicachromis-cichlids-full
• practicalfishkeeping.co.uk/features/kribensis-the-river-rainbows/
• Scherer, Ulrike & Kuhnhardt, M. & Schuett, Wiebke. (2017). Different or alike? Female rainbow kribs choose males of similar consistency and dissimilar level of boldness. Animal Behaviour. 128. 117-124. 10.1016/j.anbehav.2017.04.007.
• Nwadiaro, C.. (1985). The distribution and food habits of the dwarf African cichlid, Pelvicachromis pulcher in the River Sombreiro, Nigeria. Hydrobiologia. 121. 157-164. 10.1007/BF00008719.
• tfhmagazine.com/articles/freshwater/pelvicachromis-pulcher