What Is A Molly Fish

Before we talk about how to care for a Molly fish, let’s first find out what a Molly Fish is. A Molly fish is actually one of the most popular tropical fish for home enthusiasts. And while you may think that there is only one species of molly fish, there are actually three separate types.

mollies fish

The species includes short fin molly, sailfin molly and the Mexican sailfin molly. They generally live in brackish water a while before going back to their freshwater living areas. Unlike let's say goldfish which tend to live in cooler waters.

Short finned Mollies, in general, are an easy fish to raise. They are not demanding of their keepers, and will live quite happily in a 10 gallon tank. Sailfin Mollies, on the other hand, can be a bit more difficult to keep, if only because they are the larger of the species.

There are so many different types of Molly Fish but below we list the most common Molly fish kept in home aquariums.

  • ​Golden Sailfin Molly
  • Gold Dust Molly
  • Gold Doubloon Molly
  • Black Molly
  • Balloon Molly
  • Platinum Lyretail Molly
  • Dalmation Molly
  • Black Lyretail Molly
  • Black Sailfin Molly
  • hand-o-right
    Harlequin Sailfin Molly
  • hand-o-right
    Marble Lyretail Molly

Now that we know a few different types of Molly fish let's get ready to set up a great environment for our Mollies.

Molly Fish Tank Size

The first item to check off on your quest to raise Molly fish will be to determine a tank size. Both species of Mollies, in order to thrive and grow well, should ideally be housed in at least a 29 gallon tank.

The benefit of a larger tank is the water stability. You won’t have the sudden quality changes in the water environment that smaller tanks suffer from. This will help to ensure the health of your Molly fish.

Filtration For The Molly Fish

Filtration will be the second item you want to look into. The better the filtration, the better the water quality you will be managing. Mollies actually prefer their tank to be over-filtered, not because they are a messy fish, but rather because the hybrids can be more susceptible to disease. The best filter to purchase is a canister filter.

However, knowing that not everyone has a money tree in their backyard, purchasing a high quality filter that hangs on the tank will work as well. No matter what you choose, the one that offers excellent filtration, is very durable and long lasting, will be the one you want for your tank.

On a side note, there are some people who feel that Mollies need salt because of the time they spend in brackish water in the wild. In a human kept tank, salt is not a must have.

You will need to determine this on a case by case, or fish by fish basis. Mostly it stems from some hybrids and their susceptibility to disease. The thought was that the salt would help to keep disease at bay.

Food For Mollies

Next on your checklist is food. What food is best for your molly community? Feeding Mollies can be like feeding yourself, if you are an omnivore. First off, purchase a high quality flake food. This should be the staple of your fish feeding routine. They will also thrive on fresh zucchini coins, cucumber medallions and shelled peas that have been blanched.

Of course, not everyone has the time to do this on a daily basis, we understand that. So what do you do instead? You can purchase a spirulina based flake diet can help with supplementation.

Heating Molly Fish Tank

Heating the Molly fish tank will be the next item to look into. Because they are a tropical fish, you will want to purchase a decent heater to keep the water at a constant temperature. If they get too cold, they are more susceptible to disease.

Keep the tank at a temperature between 75 and 82 degrees F. You will want to research a heater that is rated for 5 watts for every gallon of water that your tank holds. This will ensure that the heater can work as it is designed and last longer.

Cleaning And Water Changes For Molly Fish Tank

The last item on your must do checklist, water changes and gravel cleaning. This is very important to keep the tank and your fish healthy. But, you ask, doesn’t the filtration system do all that? Yes, it does, in its own way. However, nothing is perfect. Debris and fish waste falls into the gravel and gets trapped, something the filter can’t take care of.

cleaning fish tank

So we have to do some further cleaning to help the filter out. How often you clean the gravel and change over the water depends primarily on the size of your tank and how many fish are in it.

There is a wonderful tool sold in pet stores and online that does the job easily and efficiently. It’s a water changer/gravel vacuum. How do I know it’s wonderful? I’ve used one for years. I love it and can’t recommend it enough to fish keepers.

Molly Fish Community Tank Mates

So on to getting the tank pretty and fun. What fish will work best with your molly fish? Well, you are in luck because Mollies like to be in a community. Because they are laid back, it makes them easy to get along with. The best fish mates to have are other live-bearing tropical fish.

molly fish tank mates

There are several breeds and species that will do well. A few to think about are the other molly species, guppies, female betas and the like. Whatever you choose, follow this simple rule of thumb of one inch of fish per gallon of water.

So that if you have two mollies at four inches each and two others at say, seven inches together, that would be a minimum of a 15 gallon tank.  Whether you add more or keep your fish community small definitely depends on how often you want to clean the tank. More fish equals more waste.

In the end, it also depends on the aesthetic factor. What fish you choose to keep in your tank, allows you to be free in choosing colorful combinations.

Always keep in the back of your mind the size of tank and how often you want to clean. What species will go well together based on feeding, size, and personality.

We wish you happy fish keeping.