15 Best Molly Fish Tank Mates

Looking to add some other fish to your molly fish tank but not sure which fish make the best tank mates for mollies?

by Fabian

Updated: August 2, 2023 / 13 mins read

Fabian is the dedicated Chief Editor at Aquarium Nexus. From a young age, he was captivated by the vibrant world of aquatic life, leading him to accumulate over 20 years of experience in keeping and breeding various fish species. The fulfillment derived from the aquarium hobby has remained a constant throughout Fabian's life. As an expert in the field, he finds great pleasure in imparting his extensive knowledge and personal experiences to both seasoned aficionados and budding enthusiasts.

Whenever you’re looking to add new fish to your community aquarium, there are a few things to consider like compatible water parameters, temperaments, and size.

To save you time from doing extensive research on these matters, I compiled a list of the 15 best molly fish tank mates:

1. Guppy Fish

• Compatibility: 4 out of 5
• Tank Size: 10 gallons (38 liters) minimum
• Care Level: Easy
• Temperament: Peaceful
• Diet & Feeding: Omnivorous
• Adult Size: 1.2-2.4 in (3-6 cm)

Guppies make an excellent companion for molly fish. They’re both livebearer fish, they both enjoy the water with similar parameters, and they’re both omnivorous species.

They’re also a good match when it comes to temperament. Guppy fish stay at around 2 inches and enjoy a planted aquarium with plenty of space left for swimming.

Since they can breed often, it’s best to limit the number of males to females or keep males only since they display more impressive colors compared to female guppy fish.

I especially enjoy guppy fish as they’re also very useful in controlling mosquito populations in the wild since they also feed on mosquito larvae.

Feeding guppies is quite easy as they accept a variety of foods and they have a seemingly insatiable appetite. Be careful not to overfeed them though, which can cause health problems.

2. Endlers

• Compatibility: 4 out of 5
• Tank Size: 10 gals (38 liters) minimum
• Care Level: Easy
• Temperament: Peaceful
• Diet & Feeding: Omnivorous
• Adult Size: 0.8-1.2 in (2-3 cm)

Endler fish are closely related to guppy fish so much so that they’ll even breed with them. Therefore, it makes sense that they’re also compatible fish to be kept with mollies.

Endlers are small, colorful fish that are very easy to keep. They’re just as active as mollies and will explore the entire tank rather than just hanging around at the bottom or top of the aquarium.

They display a variety of colors (yellow, orange, blue, red, purple, etc.) and they have a specific metallic green color that is present on most strains.

They’re undemanding when it comes to food, feeding on a variety of foods with the only caveat that they require smaller foods to fit their mouths. Feed them small pelletized foods, baby brine shrimp, and crushed flake foods.

3. Platy

• Compatibility: 4 out of 5
• Tank Size: 10 gals (38 liters) minimum
• Care Level: Easy
• Temperament: Peaceful
• Diet & Feeding: Omnivorous
• Adult Size: 1.5-2.5 in (4-6 cm)

Platy fish are another live-bearing fish that’s easy to care for and it’s loved by beginners for their undemanding nature.

Platies are social and enjoy being kept in groups and prefer an aquarium that’s a bit roomier as they’re active.

They reach sizes of 1.5-2 inches and feed on a variety of foods, but they do require a significant amount of vegetable matter.

These fish also breed easily, so be careful to control their population by limiting the number of males you’re adding to the aquarium if you’re keeping both genders.

They’re a good choice for molly fish and they’re compatible with lots of other fish including guppies.

4. Swordtails

• Compatibility: 4 out of 5
• Tank Size: 15 gals (57 liters) minimum
• Care Level: Easy
• Temperament: Peaceful
• Diet & Feeding: Omnivorous
• Adult Size: 4-5.5 in (10-14 cm)

Low-maintenance requirements and an oddly-shaped body make these fish an interesting addition to a community aquarium.

Although they’re available in various colors, swordtails with black tails and red bodies are the most common in home aquaria.

Some variants can be a little more aggressive especially males and especially towards other males, other variants are timid and peaceful.

Even though swordtails don’t grow big, they still require space in their aquarium because they’re active swimmers.

They require a planted tank and a covered one since they have a tendency to jump out of the tank.

Also, limit the number of males so that they don’t stress out the females too much and so that their breeding doesn’t get out of control.

Although swordtails are omnivores, they require vegetable content in their diet, so make sure you opt for flakes that have a high content of vegetable matter.

5. Neon Tetras

• Compatibility: 3.5 out of 5
• Tank Size: 10 gals (38 liters) minimum
• Care Level: Easy
• Temperament: Peaceful
• Diet & Feeding: Omnivorous
• Adult Size: 1-1.5 in (2.5-4 cm)

A popular fish among fish-keepers, the neon tetra is a colorful and vibrant fish that’s easy to care for. They have a peaceful temperament and simple dietary needs.

They reach sizes of 1.5 inches and have longer lifespans, somewhere around 8 years in the wild and around 5 years in home aquariums. Their colors include red, translucent and metallic blue.

Neon tetras enjoy a planted freshwater aquarium and the starting size of the aquarium should be at least 15 gallons.

They spend most of their time in school and prefer swimming in the middle of the water column.

Their plant should be heavily planted to create shade and hiding places. Choosing a dark substrate will create a beautiful contrast with their colors.

Because of their size, they should not be placed in the same aquarium with big fish that could eat them, and you should choose peaceful tank mates for them.

6. Zebra Danio

• Compatibility: 3 out of 5
• Tank Size: 10 gals (38 liters) minimum
• Care Level: Easy
• Temperament: Active and generally peaceful
• Diet & Feeding: Omnivorous
• Adult Size: 2-2.5 in (5-6 cm)

Zebra Danios are another interesting fish species that I would recommend even for beginners. They’re suitable for community aquariums just don’t keep them with fish that have long fins as zebra danios may nip at them. So, for good measure, choose to house them with short-finned mollies.

They enjoy swimming in the upper levels of the water column, but they’re active fish that will not shy away from exploring the entire aquarium.

They should not be housed with very mellow fish as their active nature may stress slower fish out.

In terms of food, they’re not demanding although they do have a strong preference for vegetable matter and invertebrates.

7. Minnows

• Compatibility: 3.5 out of 5
• Tank Size: 10 gals (38 liters) minimum
• Care Level: Easy
• Temperament: Peaceful
• Diet & Feeding: Omnivorous
• Adult Size: 1.5-2 in (4-5 cm) for White Cloud Mountain Minnows

Peaceful by nature, minnows make great freshwater aquarium inhabitants and can be kept with mollies, tetras, plecos, and small, peaceful community fish.

Generally, they have drab colors (silver or dull gray), but some have been selectively bred and display more impressive colors like the White Cloud Mountain Minnow, which has red coloration on its tail and even its body.

The ideal aquarium setup for minnows should include lots of live plants, rocks, and driftwood to provide lots of hiding spaces.

In the wild, minnows feed on a variety of foods including small crustaceans, plant matter, insect larvae, detritus. In captivity, they enjoy the same variety. Feed them flakes, live or frozen foods.

Minnows are egg-layers that are fairly easy to breed in home aquariums with the only caveat that they don’t show any parental care following spawning.

8. Corydoras

• Compatibility: 4 out of 5
• Tank Size: 20 gals (76 liters) minimum
• Care Level: Easy
• Temperament: Peaceful
• Diet & Feeding: Omnivorous
• Adult Size: 1-3.5 in (2.5-9 cm) depending on the species

As bottom dwellers, corydoras are a peaceful and low-maintenance community fish that are compatible with molly fish.

Corydoras enjoy scavenging for food in the substrate of the aquarium, which makes them very useful in picking up leftovers and keeping the tank clean.

You shouldn’t expect them, however, to feed primarily on leftovers and you should aim to offer them a variety of fish foods like flakes, pellets and bottom feeder tablets.

They enjoy a planted aquarium and prefer being kept in small groups rather than alone. Their aquarium should have aged water as they’re sensitive to unstable or poor water conditions.

Because they’re peaceful and otherwise undemanding, they’re compatible with many community freshwater fish including mollies and tiger barbs.

9. Birtlenose Plecos

• Compatibility: 3.5 out of 5
• Tank Size: 30 gals (113 liters) minimum for smaller species
• Care Level: Moderate
• Temperament: Mostly peaceful
• Diet & Feeding: Herbivorous
• Adult Size: 3.5 in (9 cm)

Another excellent tank cleaner, the birstlenose pleco is a bottom dweller that spends its time scavenging in the substrate picking up leftovers, and cleaning your aquarium of algae.

The only issue with plecos is that they grow larger than most fish compatible with mollies, therefore, they should be kept in 30+ gallon aquariums.

Plecos are generally peaceful, except when it comes to other pleco males towards which they exhibit territorial behaviors. They’re not aggressive or territorial with other fish species.

To curb their aggressive behavior, keep a single pleco with other community fish, and you won’t have any problems.

Algae wafers and raw veggies should be part of their diet and since they’re vigorous eaters, you should be careful not to overfeed them.

10. Gouramis

• Compatibility: 3 out of 5
• Tank Size: 20 gals (76 liters) minimum for smaller species
• Care Level: Moderate
• Temperament: Varies, can be territorial
• Diet & Feeding: Omnivorous
• Adult Size: 2-6 in (5-15 cm) depending on the species

As tropical freshwater fish, gouramis get along with molly fish, but many other community-friendly species.

They display beautiful colors and they’re relatively peaceful fish that thrive on a balanced and varied diet.

They’re only relatively peaceful because the males of the species tend to pick fights with other gourami males as well as colorful males of other fish species, therefore, make sure to monitor tank dynamics if males are present.

11. Angelfish

• Compatibility: 3 out of 5
• Tank Size: 30 gals (113 liters) minimum
• Care Level: Moderate
• Temperament: Semi-aggressive
• Diet & Feeding: Omnivorous
• Adult Size: 6 in (15 cm) body height, 8 in (20 cm) body length

Angelfish are beautiful fish popular among beginners and experienced aquarists alike.

Because of their tall bodies, angelfish prefer tall aquariums and you should be careful not to overfeed them, which can cause them a series of digestive issues.

Opt for tanks that are around 30 gallons and keep them in pairs or in groups of 5-6 in bigger aquariums.

Angelfish can become territorial when breeding and guarding their eggs, especially since they exhibit excellent parental behaviors.

Mollies, however, are well-equipped to handle a bit of conflict, so they’re not really at risk of any issues.

They can be housed with a variety of other community fish and they enjoy planted tanks that offer them enough hiding spaces.

12. Harlequin Rasbora

• Compatibility: 4 out of 5
• Tank Size: 10 gals (38 liters) minimum
• Care Level: Easy
• Temperament: Peaceful
• Diet & Feeding: Omnivorous
• Adult Size: 1.5-2 in (4-5 cm)

These vibrant fish with an easy-going nature make good tank mates for plenty of community-friendly fish including molly fish.

Harlequin rasboras have a silver body with a black patch and orange fins and reach sizes of up to 2 inches. Their lifespan is around 5-8 years.

They should be kept in large groups (8+), otherwise, they become shy, reclusive, and stressed. They’re easy to care for and prefer the top and mid-levels of the water column.

They don’t exhibit territorial behaviors and for best results, they should be fed a variety of foods — flakes, frozen or freeze-dried, and fresh foods.

13. Siamese Algae Eater

• Compatibility: 4 out of 5
• Tank Size: 20 gals (76 liters) minimum
• Care Level: Moderate
• Temperament: Peaceful
• Diet & Feeding: Omnivorous, primarily algae
• Adult Size: 4-6 in (10-15 cm)

Siamese algae eaters are excellent tank cleaners (hence the name) with the only caveat that they grow big — around 6 inches, so a bigger tank is required to house them comfortably.

They’re one of the most prolific algae eaters out there, especially since they can tackle a difficult type of algae, the black beard algae.

You shouldn’t keep a single algae eater in the aquarium, they should be kept in a school of 3-5, otherwise, they’ll become aggressive and territorial.

Siamese algae eaters are mostly herbivores and require algae wafers, cooked veggies, and flakes high in vegetable matter.

14. Otocinclus Catfish

• Compatibility: 4.5 out of 5
• Tank Size: 10 gals (38 liters) minimum
• Care Level: Moderate
• Temperament: Peaceful
• Diet & Feeding: Herbivorous, primarily algae
• Adult Size: 1.5-2 in (4-5 cm)

These busy little algae eaters enjoy well-established, stable, and mature aquariums where they can nibble on soft filmy, and soft green algae varieties.

Their diet must be completed with algae wafers and fresh veggies. They’re small fish that reach around 1.5-2 inches in adulthood.

Because they’re small and peaceful, tank mates should be chosen carefully as they cannot protect themselves. Aggressive fish and predatory fish should be avoided.

15. Snails

• Compatibility: 5 out of 5
• Tank Size: Depends on snail species
• Care Level: Easy
• Temperament: Peaceful
• Diet & Feeding: Herbivorous, primarily algae and decaying plant matter
• Adult Size: Varies by species

If you’re looking for something other than fish to add to your molly fish tank, snails are a good choice. You can include nerite snails, rabbit snails, trumpet snails, and ramshorn snails.

You should provide them coverage in the form of live plants. They will feed on soft algae that grows in the aquarium as well as leftover flakes. You should complete their diet with algae wafers and sinking pellets.

Fish That You Should Not Keep with Mollies

Not all fish and aquatic creatures make good companions for molly fish. Here are some fish that you should avoid keeping with mollies:

1.  Bettas

Bettas are territorial, plus they will attack fish with long flowing fins like the ones that mollies have, therefore, they’re not a compatible mate for mollies. Plus, their water requirements don’t match up.

2.  Goldfish

Goldfish enjoy colder water than mollies would find comfortable, but this isn’t the only reason why these two aren’t a good combo. Molly fish have been reported to bully goldfish causing injuries.

3.  Aggressive Fish

Aggressive fish should not be kept with mollies as they’ll pick fights and injure your molly fish. Barbs are generally aggressive, and they’re fin nippers that will attack the fins of your molly fish.

4.  Shrimp

You should not keep shrimp with your mollies as your fish will try to eat your shrimp. They’ll pick at them and tear them apart, so pick other mates that are compatible with molly fish.

Conclusion

If you want a healthy aquarium in which your fish get along, make sure you pick compatible mates.

Avoid keeping fin-nippers or other aggressive fish with your mollies to prevent injuries, infections and even death.

Always research the fish species you’re planning on adding to your aquarium to make sure their water requirements match up with that of your molly fish.