If you’re new to fish keeping, you might be wondering how long molly fish can go without food, especially if you don’t have anybody to look after your pet fish while you’re away.
They are generally able to go without food for up to two weeks as long as they are in good health and have a well-established appetite. However young fish can only survive for three days.
In this guide, we’ll go through everything you need to know about how long can molly fish survive without eating and what variables impact their survival duration.
How Long Does It Take Adult Molly Fish to Survive Without Fish Food?
Adult mollies can go up to two weeks without eating. They can live without food for a while due to their body composition.
Adult molly fish have a high level of body fat, which implies they may survive longer without eating because they can utilize this accumulated energy to live.
How Long Can Molly Fry Survive Without Food?
Molly fish fry only survive for three days without food. However, in an established home aquarium that provides soft algae and microfauna such as seed shrimps and daphnia, your small fish may live for much longer without fish food.
7 Factors Affect the Survival Period of Mollies Without Food
1. Size of Molly Fish
The size of your molly fish species will play a big role in how long they can safely live without food.
Larger mollies will be able to store more energy in their bodies and survive for a long periods without eating.
However, this doesn’t mean that you should overfeed your mollies leading up to your trip as this can cause health problems such as obesity and swim bladder disease.
2. Life Stage of Molly Fish
The life stage can affect the period a molly fish can survive without food.
Molly fry have a shorter survival period without food as compared to adult fish since they are still growing and developing.
As such, they require more fish food to sustain themselves which is why it’s important to not leave them for too long without food.
3. Environmental Conditions
Environmental conditions are like the wild card when it comes to how long your molly fish live without eating.
For instance, if the water temperature is low ( not lower than 72 F), their metabolism will slow down and they’ll be able to go longer without food.
Otherwise, if the water temperature is high ( not higher than 78 F), their metabolism will speed up and they’ll use up energy stores faster.
The quality of the water is also important as dirty or polluted water can lead to stress and illness which weakens the fish and shorten their survival period.
4. Type of Food
The type of food you give your fish species can influence their survival time as certain meals are more nutritious than others.
A good example is, that live food such as brine shrimp is generally more nutritious since it contains all the nutrients and energy that mollies need to survive.
On the other hand, processed foods such as pellets and flakes are often lacking in nutrients and can cause mollies to become malnourished if they are not getting enough of other food sources.
5. Molly Fish Health
The status of the fish’s health can have an impact on its survival duration in such a way that a sick or weakened fish will need to eat sooner than a healthy fish.
This is because sick or weak fish will have a lower tolerance to starvation and their body will start breaking down quickly to sustain themselves.
6. Starvation Tolerance
Starvation tolerance means the fish’s ability to withstand and survive without food.
You can know if your molly fish has a high or low tolerance to starvation by observing its behavior when you first introduce it to the aquarium.
If the aquarium fish is constantly searching for food and seems to be ravenous all the time, then it likely has a low tolerance to starvation.
On the other hand, if the aquarium fish is more laid back and not as interested in food, then it probably has a higher tolerance.
7. The Presence of Other Fish in the Aquarium
The presence of voracious tankmates can influence how long your molly may go without food.
This is because if there are other fish in the aquarium that is constantly eating all the food, then your mollies will have a harder time finding anything to eat and may end up starving.
In addition, if the other fish are much larger than your mollies, then they may bully them and steal their food which can also lead to starvation.
8 Things You Should Do to Help Mollies Survive While You Are Away
1. Clean the Filter
Cleaning the filter is one of the most important things you can do to help your mollies survive while you’re away. A dirty filter can lead to water pollution which can stress the fish and make them more susceptible to illness.
Be sure when you clean the filter not to use tap water that has chlorine in it which eliminates beneficial bacteria.
If you have a sponge filter, clean the mechanical filter and remove any accumulated debris. Also, avoid touching the biological filter to protect the healthy colony of bacteria that has formed.
2. Perform a Bigger Water Change
You should perform water changes that will help to remove as much waste and nitrates as possible, and toxins will take longer to accumulate to harmful levels.
If you perform a weekly water change of 25-30%, the day before you leave on vacation, do a 50-70% water change.
3. Set Aquarium Lights on Timer
A light timer can help to regulate the day and night cycle in your aquarium while you’re away, which can help your mollies relax.
This will also extend molly fish’s lives by allowing them to survive longer without food since they will be less active during the night.
4. Clean Your Aquarium
Cleaning the aquarium is important because it will remove any decaying organic matter that could release toxins into the water.
So make sure to remove any algae that have built up on the glass. Also, remove decaying matter or leaves, dying or sick fish, and any uneaten food, since ammonia levels can rise if decaying organic material and dead fish accumulate, leading to the death of your mollies.
5. Turn Down the Water Temperature
Turning down the temperature of your fish tank will lower the rate of metabolism in your fish, thus lowering their appetite.
However, be sure not to turn down the temperature too low, or it can lead to health problems in your mollies. The minimum temperature for molly fish is 72 degrees Fahrenheit.
6. Don’t Overstock the Tank
Overstocking can cause water fouling and an increase in metabolism due to the fish competing for food. As a result, they will require more frequent feeding.
Therefore, the best way to ensure that your fish don’t need to be fed too often while you are away is to avoid overstocking the tank.
Moreover, it is a good idea to remove any unneeded decorations as these can also contribute to fouling of the water.
7. Get Rid of Rotting Matter & Debris
Rotting matter can lead to ammonia spikes which can be lethal to your fish.
Ammonia spikes will stimulate the appetite of your fish, thus leading to an increase in the number of meals that they will need.
Uneaten food and debris can also lead to ammonia spikes as they decompose.
Therefore, it is important to remove any rotting matter or debris before you leave so that your fish will not starve too soon.
8. Don’t Overfeed Your Molly Fish
Overfeeding is one of the most common mistakes that people make when it comes to fish care.
A lot of people think that if they give them an extra meal, their fish will be fine. However, this is not the case.
Overfeeding your fish will lead to producing more waste and fouling the water. This can be lethal to your fish as it can lead to ammonia spikes.
Additionally, overfed fish are more likely to become obese and develop health problems.
What Should You Do If You Are Leaving Your Mollies for a Long Time?
1. Fish sitters
If you’re not able to take your fish with you, a well-prepared sitter who provides clear instructions on how to care for your pet fish and fish keeping while you’re gone is the best way to ensure their safety.
A friend or family member who’s willing to check in on your fish daily is ideal. If that’s not possible, consider hiring a professional fish sitter.
You can leave a detailed list of everything you need in case the sitter forgets something. Also, leave your phone number and email address so that he may get back to you quickly if there is an emergency.
If you can’t get a fish sitter, consider setting up a vacation feeder. This is a commercialized slow-release feeding block.
Vacation feeders come in a variety of forms and sizes, and they’re meant to feed your fish for set lengths of time.
However, the major drawback of these is that the food they contain may not be what your fish are used to eating.
Automatic feeders are designed to hold and dispense free-dried or dry food items.
They are available in a range of designs and can be programmed to feed your tropical fish once a day or every few days.
It’s simple to use and comes with a nice digital display. You can regulate the quantity of food supplied in each feeding, and it will keep your fish fed for weeks.
While the promise of feeding your fish automatically is appealing, it’s critical to realize that if the filter breaks down, continuous dispensing of food will lead to an unclean aquarium. This may eventually kill your fish.
Should You Use an Automatic Feeder for Your Molly Fish Tank?
Yes. If you are leaving your tropical fish for up to a week, we recommend using an automatic fish feeder.
However, while they are an excellent tool for these circumstances, I wouldn’t advocate them as a replacement for the needs of adult fish.
The trouble is that since you are not present to execute water changes and maintain the tank, molly fish that eat normally will generate uncleaned waste.
But, things are somewhat different for baby fish since they don’t produce much waste.
Mollies are resilient fish that can survive without food for a while.
However, having a well-maintained tank will help your molly fish survive longer without any problems.
We hope you enjoyed reading this article. If you have any questions or comments, please feel free to leave them below.