Dalmatian Molly Care Guide | All That You Need To Know!

Dec 27, 2021

dalmatian molly

If you thought dogs and cows were the only animals to spot iconic black and white spots, you’re in for a treat, my friend. Meet dalmatian molly – hands down the most beautiful fish you’ve ever seen. 

I love these fish because their personalities are just as pleasant as their looks. They’re hardy, friendly, and everything nice. 

In this article, I will share everything there’s to know about dalmatian molly so you can provide them with the best care they deserve. 

Let’s begin with a brief overview!

Dalmatian Molly Overview 

Name Dalmatian molly
Scientific Name Poecilia latipinna 
Family Poeciliidae 
Genus Poecilia 
Color Black and white spots 
Max Size 5 inches 
Care Easy
Breeding Easy
Diet Omnivore
Temperament Peaceful
Temperature 68-82°F (20-27°C)
pH 7.0-7.8
Tank Size 30 gallons

Mollies were first introduced in the aquarium hobby in the 1800s. Several unique varieties started to appear in the 1920s. 

Dalmatian mollies are believed to be the hybrids of the popular sailfin mollies that originally inhabit the freshwater habitats from North Carolina to Texas and the Mexican Yucatan Peninsula. 

Even though hybridized mollies are abundant in artificial settings, they aren’t usually seen in the wild. 

All the different species of molly fish can hybridize with one another. And that’s the reason there are so many different color morphs, patterns, and shapes that exist today. 

Selective breeding has indeed produced the most dazzling array of colors and patterns like the dalmatian molly. 

Dalmatian Molly Lifespan 

The average lifespan of a dalmatian molly is 2 to 5 years in captivity. The kind of environment they’re in, the diet they’re being fed, and their genetics play a crucial role in determining their lifespan.

Their wild cousins have a pretty short lifespan. Typically, they only live for a year after reaching sexual maturity – and mind you, these fish reach sexual maturity pretty fast. 

In nature, fish that breed constantly and prolifically tend to have a short lifespan. 

Also, males die sooner than females as they’re more prone to predation due to their small stature. 

Dalmatian Molly Appearance 

Dalmatian mollies most likely inherited their iconic black and white spotted coloration from the spotted form of a sailfin molly, Poecilia latipinna. 

As the moniker gives away, these fish sport unique black and white spots like the dalmatian dog, which sets them apart from other molly types. 

These fish have chunky, thick-set bodies. The heads and mouths have a pointed shape. The tails are convex. 

The dorsal fin is tall and angular. Male dalmatian mollies often raise their dorsal fin to threaten rival males or impress potential mates. 

Dalmatian mollies have upturned mouths that help exploit films of oxygen-rich surface water. Therefore, they are super tolerant and can survive even in oxygen-depleted environments. 

Likewise, the jaws protrude slightly forward – making them a scraping tool ideal for rasp algae from rocks and plants. 

Based on the appearance (mainly shape), dalmatian mollies can be broadly divided into 4 types. Let’s have a quick look at them. 

4 Types Of Dalmatian Molly 

The four types of dalmatian mollies that each sport unique shapes and features are:

  • Standard dalmatian molly 
  • Balloon dalmatian molly
  • Lyretail dalmatian molly 
  • Sailfin dalmatian molly

Standard Dalmatian Molly 

The standard dalmatian molly has the same stature and coloration as the common molly. However, the shiny silver scales are decorated with beautiful black spots. 

These fish can grow around 5 inches long. And they live 3-5 years if the right care is provided. 

Balloon Dalmatian Molly 

dalmatian balloon molly
Credits: Sarah Altendorf (Creative Commons license)

Balloon dalmatian molly was bred to have a short, round appearance like an inflated balloon. Therefore, the fish has a steeply arched back, a rounded belly, and a lyre-shaped caudal fin. 

However, beauty comes with a price. A dalmatian molly’s spine is deformed, and internal organs are compressed. Therefore, they’re more susceptible to contracting health conditions than other variants. 

These fish only grow around 3 inches long and can live for 2-5 years. However, the mortality rate is relatively high with these fish. 

If you’re interested to read up on the cruel dying process these fish go through and some more, don’t forget to check out this article. 

You May Also Like: Everything You Need To Know About Balloon Belly Molly

Lyretail Dalmatian Molly 

lyretail dalmatian molly
Credits: Segrest Farms (Creative Commons license)

Lyretail dalmatian mollies are the color morphs of the OG sailfin mollies. The standout feature in these fish is their lyre-shaped caudal fin. 

The black and white patterned scales give these fish a unique marbled appearance. 

In captivity, they grow around 3 inches long and have an average lifespan of 2-5 years. 

Sailfin Dalmatian Molly

sailfin dalmatian molly
Credits: Corpse89 (Creative Commons license)

Sailfin dalmatian mollies boast a tall and large dorsal fin that runs from the back of the head all the way to the caudal fin. Like other fish on the list, they have beautiful black spots that complete their look. 

Sailfin dalmatian mollies grow around 4-5 inches long and live for about 3-5 years.

Recommended Readings!

How Many Babies Do Mollies Have? Record-Breaking Number!

How Many Mollies In A 10-Gallon Tank? It’s Not Really Recommended!

How To Tell If A Molly Fish Is Dying? Look For These Signs!

Dalmatian Molly Size 

Dalmatian molly can grow anywhere between 3-5 inches in captivity. Balloon and lyretail dalmatian mollies usually clock in around 3 inches, whereas standard and sailfin dalmatian mollies can grow as long as 5 inches. 

Genetics is the most important aspect at play here. Usually, breeders tend to prioritize colors over size for hybrids like dalmatian mollies. 

Also, fish farmers make more dough from fish that breed when young (and thus relatively small) than those fish that grow more slowly (and most probably big). 

Hence, the end result is that farmed mollies varieties are significantly smaller than their wild cousins. 

That being said, the diet and environment also play essential roles in determining how big your dalmatian molly can get. 

For example, a small tank can stunt the fish’s growth and prevent it from reaching its true potential size. More on that below! 

Dalmatian Molly Temperament 

Dalmation mollies are friendly and sociable fish that do exceedingly well in any community aquarium. They’re also active swimmers with a great affinity for exploration. Therefore, they do well in large tanks with numerous decorations. 

Unlike most fish, dalmatian mollies don’t school. In fact, they’re shoaling fish. And what it means is although they travel in big groups, they do so for social purposes instead of traveling in specific directions with each other. 

Interestingly, one-quarter of all fish shoal their entire lives; molly is one of them – shoaling in a group of thousands in the wild. 

So, you can expect to see this behavior in the tank too. 

Although peaceful for the most part, dalmatian mollies are known to nip fins when they’re in a bad mood. This is especially true for males, who will nip fins of other males to exert dominance, or females to coax them into mating.

Males are also known to establish hierarchies and pecking order. So, if you have a sharp mind and some time to kill, it could be interesting to watch social interactions.

Dalmatian mollies are diurnal creatures just like us. They remain awake and active during the daytime and are asleep when the night falls.

They are non-aggressive and easy-going most of the time. However, they can get mean if the tank’s too crowded or when they’re competing for a partner. 

Lastly, dalmatian mollies don’t make good parents. They will eat their young ones at every chance they get. Yikes! 

Since parents don’t provide any care, the fry are born ready to fend for themselves and hide. It just comes naturally to them. Impressive! 

Dalmatian Molly Tankmates 

Ideally, dalmatian mollies would love to be with their own kind. But since they’re friendly and non-aggressive, they can be placed with other fish with a similar temperament. 

Here’s a list of tankmates that are compatible with dalmatian mollies:

  • Guppies 
  • Corys 
  • Platies 
  • Swordtails 
  • Dwarf gouramis 
  • Neon tetras 
  • Catfish 
  • Zebra loaches 
  • Rosy barbs 
  • Cherry barbs 
  • Shrimps 
  • Snails 

Dalmatian mollies are fin nippers. Therefore, they shouldn’t be placed with fish that sport distinguished fins like bettas and angelfish. 

Also, as they are not on the aggressive side, they cannot hold their ground if placed alongside aggressive fish like firemouths, green terrors, oscars, and convicts. 

Water Parameters For Dalmatian Molly 

Temperature 68-82°F (20-27°C)
pH 7.0-7.8
General Hardness 12-25 dGH (200-416 ppm)
Carbonate Hardness 10-25 dKH (178-450 ppm)
Ammonia 0 ppm
Nitrite 0 ppm
Nitrate Less than 20 ppm
Water Flow Moderate
Swimming Region Top and middle 

Tank Maintenance For Balloon Molly 

In the wild, mollies love to live in shallow surface waters. So, expect to find the fish swimming in the middle and top area most of the time. 

Dalmatian mollies bred in commercial settings can fare well in both freshwater and brackish water, given that other parameters are correct – especially water quality and hardness. 

Mollies are extremely hardy fish. They can quickly adapt to an array of seemingly extreme conditions ranging from low oxygen levels, high salinity, and even high concentrations of hydrogen sulfide that would kill most fish instantly. 

However, it doesn’t mean you can, or you should put the fish to the test. 

The ammonia, nitrite, and nitrate levels in the tank should always be clocked in at 0 ppm. 

To give you an example, if the ammonia levels are high, it will destroy the protective mucous layer that protects the fish’s body. As a result, your fish will be vulnerable to numerous deadly pathogens waiting for the right time to strike. 

From what I have read, dalmatian mollies are especially sensitive to nitrate. Therefore, always aim to have the nitrate levels below 20 ppm at all times. 

Frequent water changes will help you with this. Stocking plants and feeding the fish sparingly (especially protein-rich food like bloodworms) can help keep the water clean and healthy for longer durations. 

Here’s a quick rundown of things you should do daily, weekly/biweekly, and monthly. Note that the list below isn’t entirely conclusive. 

Daily Tasks 

  • Do a headcount and observe the fish for any signs of abnormality 
  • Check the filtration equipment 
  • Check the heating system and read the temperature 
  • Top off the water level 
  • Promptly remove uneaten food 
  • Note any concerns in a logbook 

Weekly/Biweekly Tasks 

  • Monitor water parameters 
  • Wipe down tank’s outside surface with non-ammonia cleanser 
  • Shake off debris from plants and decors 
  • Scrape the inside glass to remove algae 
  • Siphon the substrate 
  • Perform a partial water change 
  • Note any concerns in a logbook 

Monthly Tasks 

  • Perform water tests using a liquid-based test 
  • Trim live plants as needed 
  • Deep clean decors and rocks 
  • Inspect tubing 
  • Change filter media 
  • Carry out weekly/biweekly tasks 
  • Fertilize plants as required 

A quick product recommendation: API Freshwater Master Test Kit 

API freshwater master test kit

We swear by this one. A liquid-based test is more accurate and reliable than strip tests. 

Osmosis In Dalmatian Mollies 

When fish are kept in freshwater, they lose salt from their body and gain water through a process known as osmosis. The exact opposite of this happens in seawater – the fish absorbs salt and loses water.

If not intervened in time, either can be fatal. In the first case, the fish will swell up with water; in the second case, the fish becomes dehydrated. 

Impressively, mollies are euryhaline, which means they can swiftly adjust their bodies to live in both fresh and saline conditions. From what I have read on forums, they’ve even been perfectly kept and bred in full-strength seawater. 

Dalmatian Molly’s Amazing Respiration Ability

Like most fish, mollies breathe by extracting oxygen from water and pumping it through their gill cavities. 

What sets them apart is their ability to put up with stagnant, low-oxygen water than most livebearers. Mollies will swim to the top and pump the uppermost water layer that contains most oxygen across their gills. 

They can even increase the amount of hemoglobin in their blood to absorb more oxygen from water effectively. 

However, it’s never a good idea to force mollies to respire this way in an aquarium. An air pump is crucial for their well-being.

Salt For Dalmatian Molly 

If exposed to soft, acidic conditions, mollies can develop bacterial and fungal infections. A small amount of tonic salt can help control the situation. Tonic salt is basically sodium chloride. 

The recommended dosage is one to two teaspoons per 10 liters/2.1 gallons. 

Minimum Recommended Tank Size For Dalmatian Molly

Dalmatian mollies are active fish that need plenty of space. On top of that, they’re voracious eaters that produce a good amount of bioload on a daily basis. So even though they’re advertised as fish suitable for small tanks, they aren’t. 

As they are shoaling fish, they need to at least be kept in a group of 4 or more. Therefore, a 30-gallon tank would be ideal for that. 

Although you could add 2 dalmatian mollies in a 10-gallon tank if you were to follow the ‘one inch per gallon’ rule, this is strictly not recommended. 

This rule doesn’t take the space taken by decors, plants, and substrate into account during calculation. Therefore, it’s best not to apply this rule. 

I’ll briefly lay down the points that explain why you should opt for a larger tank whenever possible. 

  • Small tanks have even smaller room for mistakes. 
  • The concentration of harmful compounds builds up fast in a small tank. 
  • Even the slightest change in one area has a ripple effect in the entire tank.
  • Smaller tanks have a stronger concentration of growth-inhibiting pheromones. 
  • Small tanks don’t provide enough room for exercise and exploration. 
  • Small tanks stress out the fish. 

Substrate And Decor For Dalmatian Molly 

A sandy substrate is preferable for dalmatian mollies. My pick would be aragonite sand since it disperses minerals into the water that mollies need. 

They love to stay under floating vegetation or near structures to protect themselves better against predators. Keep this in mind when you’re sorting out the decors. 

Our picks for floating aquarium plants for your dalmatian mollies would be hornwort, java moss, amazon frogbit, and duckweed. 

However, dalmatian mollies need the addition of salt in water as they age, which might not be favorable for plants. So, keep that in mind while choosing the plant. 

Add rocks and caves that will not just make your tank look prettier but also provide a safe haven when they need some alone time. 

Just make sure that you don’t use driftwood, as this will lower the water’s pH and make it acidic. Acidic water can legit burn your dalmatian molly’s skin. 

Recommended Equipment For Dalmatian Molly 

We scoured through the internet, read all the reviews, so you don’t have to, and have come up with our choice of equipment for dalmatian mollies. 

Our list includes a canister filter, a heater, and a breeding box that’s useful to raise fry. 

Penn-Plax Cascade Canister Filter 

penn-plax cascade canister filter

Pros: 

  • Good value for money 
  • Powerful – functions at 185 GPH
  • 2 large capacity media baskets 
  • Flow valves rotate 360-degrees for easy maneuvering 

Cons:

  • Can be noisy 
  • Can be tough to reach customer service 

Hygger Titanium Aquarium Heater 

hygger titanium aquarium heater

Pros: 

  • Fully automatic control system
  • Durable titanium tube 
  • Versatile temperature range from 32-104 degrees F

Cons:

  • Heating element can fall off the glass 

Fluval Multi-Chamber Holding And Breeding Box 

Fluval holding and breeding box

Pros: 

  • Space-saving design 
  • Ensures good water circulation 
  • Great for acclimatization and raising fry 

Cons:

  • Small fry can get flushed out through the gap
  • Unclear instructions 

Dalmatian Molly Diet 

Dalmatian mollies are technically omnivores as they are known to consume both plant materials and meaty food like worms, insects, and small crustaceans. 

However, their diet overwhelmingly consists of plant material – to the point that they can practically be considered herbivores. They especially love nibbling on algae. 

For a staple diet, spirulina flakes and pellets can make great options, whereas meaty food like bloodworms should be given sparingly – once or twice a week at most – even though your mollies will consume them greedily. 

A brightly lit tank may have enough algae growth to fulfill your dalmatian molly’s needs. If that’s not the case, fortify with other algae-based food like tablets and wafers. 

Meaty food like bloodworms would only be a very minor part of their diet in the wild. Therefore, it’d be wise not to give these types of food frequently. 

Here’s a pretty wholesome list of food dalmatian mollies can eat:

  • Flake food 
  • Pellets 
  • Algae wafers 
  • Algae tablets 
  • Boiled veggies like cauliflower, zucchini, and peas 
  • Brine shrimp 
  • Aquatic plants 
  • Worms 
  • Crickets

As for feeding frequency, give two big meals or 3-4 small meals a day. And always remove any leftover food as soon as they’re done eating. 

Here’s a link to algae wafers by Hikari USA:

hikari algae wafers

Breeding Dalmation Molly

Breeding dalmatian molly doesn’t require any special effort. These fish breed readily and quite prolifically. However, if you want to encourage them to breed, slightly increasing the water temperature, feeding a protein-rich diet, and performing a water change can do the trick. 

Also, note that dalmatian mollies can hybridize with all other species of the molly fish. It can result in an assortment of colors, patterns, and tail shapes. 

Before we get into the nitty-gritty, here’s a lovely video of a dalmatian molly giving birth:

Dalmatian Molly Male VS Female 

Male mollies tend to be much smaller than their female counterparts. Males also have a specialized anal fin that’s called gonopodium. Females have regular anal fins. 

The male’s gonopodium is its biggest distinguishing characteristic. The females also have a gravid spot. However, it’s hard to spot it due to the unique patterns on their bodies. 

Dalmation Molly Male To Female Ratio 

The ideal male-to-female ratio in dalmatian mollies would be 1 male for every 2-3 females. During the breeding season, males are known to mercilessly bully the females into mating.

Thus, a higher number of females ensures that the aggression they receive is spread out evenly.

When Do Dalmatian Mollies Sexually Mature? 

Dalmatian mollies sexually mature by the age of 4-5 months generally. If you’re not looking forward to raising their fry, you should separate the males and females before reaching this age. 

Dalmatian Molly Spawning 

Dalmatian mollies, like the rest of the mollies, are livebearers. And if the environment is conducive, they can breed like rabbits. I’m really not exaggerating. They can breed once every 30-45 days and produce anywhere between 40-100 fry. 

Usually, older and experienced females give birth to a higher number of fry and have a shorter gestation period. 

The breeding tank for dalmatian mollies should at least have a capacity of 25 gallons. Additionally, it should be equipped with proper filtration, heating, aeration, and bright lights to encourage algae growth. 

Dalmatian mollies don’t form monogamous pairs. Males will try to mate with any female they can lay their eyes on. Flashing, shimmying, and nipping are some parts of the male’s ‘courting’ process. 

He will use specialized anal fins that double as narrow copulatory organs to deposit sperm into the female mollies. 

Females are fertilized internally. And they can store the sperm inside their system for up to a few months at a time. 

This unique adaptation is evolved to ensure that their population doesn’t dwindle even when male mollies are scared away from the group. 

How Long Are Dalmatian Mollies Pregnant For?

A dalmatian molly’s gestation period lasts from 40 to 70 days. The older and more experienced the female is, the shorter will be her gestation. However, the environment and level of stress also play a determining role. 

How To Know If Dalmatian Molly Is Pregnant?

The most obvious signs of pregnancy in dalmatian mollies are:

  • Distended and swollen belly 
  • Increased appetite 
  • A noticeable gravid spot 
  • Aggressive behavior 
  • Strong bulge beneath the gills 

Do Dalmatian Mollies Eat Their Babies?

Yes, dalmatian mollies eat their young ones. 

The three proposed reasons behind this phenomenon are:

  • A spill-over response triggered by stress 
  • A process of weeding out weaklings 
  • An effort to replenish the fat storage 

How To Care For Dalmatian Molly Fry?

Ideally, dalmatian fry should be housed in a 10-gallon tank. You don’t need to get a big tank as it will only make it difficult for the fry to find their food. 

The tank should have a sponge filter so that little fry aren’t sucked in. 

You should also install a heater and an air pump to ensure stable temperature and proper aeration. 

Leave the tank bare so the fry can find their food easily. You can also give decors and plants a miss. 

You can feed them pulverized flake food, boiled egg yolk’s paste, baby brine shrimp, and daphnia. You can also fortify the diet occasionally with microworms. 

Final Words: Dalmatian Molly Care Guide 

Dalmatian mollies are stunning to look at and easy to care for. If you’ve brought some, congratulations! If not, what are you waiting for??!

Dalmatian mollies are hybridized from sailfin mollies. Therefore, you cannot find them in the wild. 

They don’t require any special care as long as you maintain the right environment and diet at all times. Also, they breed quickly and quite readily. 

We hope this care guide at least answered some of your questions. Good luck! 

Recommended Readings!

How To Care For Pregnant Black Molly Fish?

How Long Do Mollies Live? Extend Their Lifespan!

How Long Are Molly Fish Pregnant For? Twice As Long As Guppies!

What Do Molly Fish Eggs Look Like? Little Yellow Balls!

rohit gurung author at urbanfishkeeping

About Rohit Gurung

My never-ending love and fascination with Aquascaping started when I received a red-eared turtle for my 10th birthday.

Apart from researching and writing, I spend hours gazing at my 3 turtles. And yeah, I bask alongside them too.