Why Does Molly Fish Lay On Rocks? Is It Safe???

Why Does Molly Fish Lay On Rocks?

Molly fish is a bright-colored fish that belongs to the “Poecilidae” family. These fish are prevalent due to their unique attribute and easy-going nature. Moreover, Molly fish also show an unusual habit of laying diploid eggs on the plants and rocks. But do you know why Molly fish lay eggs on rocks?

Molly fish lay eggs on the rocks because they are very protective parents. They also lay eggs on the rocks to keep them safe from other fish who will eat the eggs. Mollies will typically lay hundreds of eggs all over each other in small areas so that both males and females can defend the egg cluster together.

In this post, I will be explaining the various reasons why Molly fish lay eggs on the rocks. Hopefully, you will find this post interesting and informative.

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How Do Molly Fish Reproduce?

Molly Fish can reproduce in several ways. Most Molly fish reproduces sexually, like humans and most other animals. Some others also reproduce asexually, but not within the same species.

If you keep them with other spaces, they usually cross-breed to create another species. But you will get healthier and happier Mollies if you breed them with their species.

Sexual Reproduction In Molly Fish

Molly fish release hundreds of eggs at a time. After the male releases sperm into the water, the female lays the eggs immediately after mating. Molly fish lay their eggs in plants at night because they prefer softer water to protect their eggs.

Molly fish usually lay their eggs on soft leaves or in the safety of a cave. These fish do not guard their eggs during mating, and they leave the nest after copulation to search for food.

Asexual Reproduction In Molly Fish

Molly fish breed asexually, when they mate with different species of Mollies. Therefore, they always cross-breed with another species closely related to them. In addition, these fish create a particular type of egg, called a gynogenesis egg, which has two cells: one from the male and one from the female Molly fish.

Molly fish only create gynogenesis eggs when they breed with Molly fish of a different species. The egg only has the female Molly fish’s DNA. These fish develop eggs in their ovaries.

Molly fish can also reproduce sexually with Molly fish of a different species, which have their own complete DNA strand. However, they do not often cross-breed because Molly fish prefer to breed within their species.

Do Molly Fish Lay Eggs?

Molly Fish are egg layers. These fish lay their eggs underneath plants, rocks, or other objects in the tank. They will also deposit their eggs on the water’s surface if they do not have any plants to attach them to.

Molly fish eggs hatch quickly, and Molly fry looks like little minnows swimming around in your tank. These fish can lay several batches of eggs throughout their life. Egg-laying Molly Fish will release their eggs about every ten days. If you remove all the eggs from your tank, your Molly will lay more eggs.

When Do Molly Fish Lay Eggs?

Molly fish can grow up to 4 inches long. They produce tens of thousands of eggs every year. Therefore, Molly fish can lay many clutches during their lifetime. They can live up to 6years in perfect conditions, but the average lifespan is around 3-5 years.

Molly will start laying eggs when they are around one year old. These fish lay eggs around 12 hours before the sun comes up. Then, they bury their eggs in the substrate (sand, gravel, or rock).

Molly fish prefer to spawn in aquariums with 10 gallons of water or more that contain plenty of plants for them to hide & swim through. These fish love to eat their eggs, so Molly fish lovers usually remove the eggs after 5 to 7 days. Moreover, these fish need low water changes (10% per week) and nutritional sources like flake food, brine shrimp & blood worms while breeding.

Where Do Molly Fish Lay Their Eggs?

Molly fish lay their eggs in a jelly-like clump. Their eggs look like tiny dots, and the female Molly lays them at night. These fish might eat each other’s eggs under rocks. So you would want to keep their eggs in an aquarium tank that has rocks and plants. The most common places where Molly fish lay eggs are:

  • Molly fish lay their eggs on the bottom of the tank.
  • They also lay eggs on aquarium plants. But Molly fish eggs are not bright enough to be visible through light-colored leaves.
  • Molly fish could also lay their eggs under rocks or decorations in the tank.
  • These fish might also lay eggs outside in a pond or lake. But it is harder to take care of Molly fish eggs.

Why Do Molly Fish Lay Eggs On The Rocks?

Molly fish lay their eggs on the rocks to ensure that they survive. Unfortunately, these fish are egg-scatterers, and adding other fish species to your tank could result in them eating Molly fry (baby fish). Like other fish parents, Molly parents will do anything to keep their young safe both inside and outside of the eggs. Their eggs are very sticky and adhere very well to the rocks and substrate in your tank.

Some of the reasons why Molly fish lay eggs on the rocks are:

To Protect Their Younger Ones

Molly fish will lay their eggs on the rocks as a means of protection. Adding other types of fish to your tank can eat the fry. Like other fish parents, Molly parents will do anything to keep their young safe both inside and outside of the eggs. Their eggs are very sticky and adhere very well to the rocks and substrate in your tank.

These fish lay their eggs on the rocks as a means of protection against predators. Unfortunately, they also scatter them just about anywhere so they never know where to look for their baby Molly fish.

Easier Parent Feeding

Molly fish often come together with other species in some aquariums. This is because the parents do not like to leave their eggs alone while looking for food. They would rather stay close to their fry, keeping them safe and feeding them simultaneously. So Molly fish lay eggs on the rocks as a means of protection and because they like to stay close.

To Increase Their Chance Of Survival

Molly fish believe that if they lay their eggs on the rocks or even close to it, their chances of survival increase. So these fish lay their eggs on rocks and other surfaces close to the water to keep them safe from predators.

Molly fish instinctively know that fry’s chances of survival increase if they stay close by while protecting their offspring.

For To Stay Close

Molly parents also know that they should not leave their fry for long. So, they will not leave the fry too long when they go hunting prey or gulping oxygen. These fish instinctively know that Molly fry is safe if they lay their eggs on or near the rocks in your tank. 

Molly Fish Lay On Rocks To Keep The Eggs Warm

Molly fish lay on the rocks to keep the eggs warm. Molly Fish will make nests for their fry in all types of substrate. However, these Fish are not picky about what they use to build nests with.

Molly Fish will use gravel, sand, or plant materials like grass or leaves. They lay their eggs on the bottom of algae-covered rocks. It is because this helps the eggs to remain warmer and safer. Besides this, rocks also provide the eggs their perfect environment to hatch.

Some FAQs

Do All Molly Fish Lay Eggs?

Molly fish are livebearers, which means that they produce eggs and give birth to live young. These fish can’t lay their eggs on the substrate of your tank because the fry would die when they hatch. Instead, they prefer to drop their eggs in plants or other objects with enough water flow to carry the gametes (eggs) for fertilization.

What Triggers Molly Fish To Release Eggs?

Molly fish will only release their eggs when they are in good conditions with lots of food and proper water conditions. Molly fish release their eggs when there is a drop in the pH level, which triggers them to try and find a suitable location to lay their eggs.

What Are Molly Fish Eggs Like?

Molly fish eggs are roughly 1mm in diameter and don’t look like the Molly fish fry that hatch from them. Their eggs are usually completely transparent but can have some pigment to them that gives them slight coloration.

Molly fish eggs will become cloudy as they age and start to rot. So if you see Molly fish eggs that are cloudy it’s best to remove them from your tank.

How Long Do Molly Fish Eggs Take To Hatch?

Molly fish eggs take about 5-10 days to hatch, depending on the Molly fish’s age and water temperature. Molly fish fry is even more transparent than Molly fish eggs. Their fry will swim around like other baby fish because Molly fish are born with a yolk sack that they live off of for about 3-4 days after birth. The yolk sacks absorb back into the Molly fish fry’s body after they feed entirely off of it.

Conclusion

In conclusion, Molly fish are great additions to any home aquarium. They can live up to five years, and Molly fry takes approximately four months before maturing. These fish often thrive in communities where there is ample food or other factors like rock formations. They are peaceful fish, and breeding usually occurs in any aquarium as Molly fish reproduce quickly.

I hope this article has helped you out when considering getting a Molly for your aquarium.

Stay tuned for more articles coming soon!

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