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How Many Platies in a 10 Gallon Tank? (Read This First!)

Platies are beautiful small fish that come in almost every possible color. But can you keep many of them mindlessly in a 10 gallon tank? Of course not! Every fish needs their space to move, feed and live freely. So how many platies can live in a 10 gallon tank? 

This article will dive deep into the tank requirements and provide essential information about platies.

How many platies in a 10 gallon tank?

A 10 gallon tank will be suitable for five adult platies. By keeping 5 in a 10 gallon tank, they will be able to live a comfortable life, and the fishkeeper wouldn’t have to work on maintenance frequently. Build a nursery tank, as the platies will give birth every month.

Platies are life bearer fish, and they are very popular aquarium fish around the world. Their colorful appearance and various fin shapes make them a great addition to your aquarium. So, how many of them can you keep in a 10 gallon tank?

A 10 gallon tank is suitable for five platies. Platies may be small, but you also need to understand that they will have to live their whole life in that aquarium. You should not keep a lot of them just because you like to watch a lot of fish.

By keeping five platies in a 10 gallon tank, each fish will get less than two gallons of water. A 10 gallon tank is the smallest size of permanent tank for platies. 

In a 10 gallon tank, you will get the freedom of arranging the tank as you wish. You can add plants, substrate and decorative rocks. Filter and heater are also vital components of a platy tank, taking up space.

Platies are very social fish, and they love to roam around in the middle part of the tank with their friends, although they are not schooling fish. Keeping five platies will keep them socially happy, and they will not have any problem living there.

Moreover, the waste of five fish will not make the water bad too fast, so you will not have to change the water frequently. The tank will have a decent nitrogen cycle that will make the water less harmful to the fish.

But if you keep more platies in the tank, they will not have enough room for the fish to swim and play. The fish will be prone to infectious diseases, and you may lose your fish early.

If you keep platy fry or juvenile, you will be able to keep at about 15-20 platies in a 10 gallon tank, but that’s not a wise thing to do as the platies grow very fast, and you will need more tanks for them within a month. 

If you take good care of your platy fry, they will become adults within 3-4 months.

A 10 gallon tank is also perfect for a nursery tank. The fishes will get ample space to swim and grow very fast. So, if you are into breeding platies, you can get 2-3 ten-gallon tanks for the project. Wide tanks are preferable for the platies, allowing the fish to swim around with ease. 

Fish gender also matters. From five fish, don’t keep more than two males while only one is enough. Male fish always poke female fish for mates, which can be very stressful for the female fish. Less male fish is essential for a happy community.

How many platies and mollies can I put in a 10 gallon tank?

Mollies are the larger species among the three major life bearer fish species, and they can grow 3-4.5 inches. A 10 gallon tank is suitable for only three mollies. But if you want to keep platy and molly together, keep a pair of platy and a pair of Molly

Platy and Molly are from two different fish families, so they do not breed and make hybrids. But if you keep guppy and molly, you can get hybrids of guppy and molly.

Platies and mollies have similar food habits and behaviors. They also have similar temperature requirements to be good tank mates. 

But a tank with 20+ gallons of water will be better for them. In a bigger tank, you will be able to keep more platies and mollies together, which will help to build a healthy fish community.

But in a 10 gallon tank, you will not be able to keep more than a pair of fish, which is possible but not the ideal thing to do.

How many guppies and platies can you have in a 10 gallon tank?

Guppies and platies are about similar sizes. Guppies are slightly smaller than platies. So a 10 gallon tank can comfortably inhabit three platies and three guppies. Keep one male fish for each species. 

A planted tank is recommended if you want to save the fish. Both fish eat the baby fish as a snack. By producing a lot of aquatic plants, you will be able to save some of the fries. Get a breeding tank with a breeding setup if you want to save all the fries.

Platy and guppy are hardy and excellent choices for the new fish keepers. They both are fast swimmers, so there will be no competition for food.

4 factors that determine how many platies can be kept in a 10 gallon tank

You can keep five adult platies in a 10 gallon tank. Here are the factors determining the number of platies you can keep in a 10 gallon tank.

Fish per gallon:

To determine the number of fish in a tank, a rule of thumb is one gallon of water for every one inch of fish. Platies can grow up to two inches so every fish will need at least 2 gallons of water for each platy fish. That’s how five platies can live in a 10 gallon tank. 

How much time do you have:

You will have to change the water of a 10 gallon tank with five platies every seven days. But if you keep 3, you will get at least ten days between the water changes. 

You can keep a few more than five fish in some situations, but you will have to work on your tank frequently to keep the fish healthy.

More fish means more waste, and the waste is the leading cause of fish pushing away. So you have to be attentive to the responsibilities of your fish tank.

Size of your fish:

You can keep a lot of small platies in a tank. Platies give birth to 20-40 babies every month. So a 10 gallon tank will be suitable for a batch of platy fish for two months. The baby platies will grow bigger and no longer fit in a 10 gallon tank in two months. 


If you want to decorate your aquarium heavily or create an aquascape, you should keep 3-4 platies in the tank. 

How many platies per gallon?

Half a platy per gallon (two gallons of water for each adult platy) is suitable for a permanent platy tank.  One gallon of water for one inch of fish works for the platies, although some fish create more waste and need more water to live.

However, I can tell you from my personal experience that it’s hard to maintain the number of platies. You will get more than 20 fishes from each female platies every month. So you will quickly run out of nursery tanks. 

The good thing is, you can earn some money if you can sell the platy fries. It may not be much, but the space problem will be solved.

What fish can be kept together with platies in a 10 gallon tank?

Platies can live with many types of fish, but a 10 gallon tank is not totally suitable for keeping a variety of fish with platies. Here are the top fish you can keep with platies.


Guppies and platies have similar requirements, and they both are peaceful fish. You can keep them together in a 10 gallon tank.


You can keep a solo Betta in a 10 gallon platy tank.


You can keep a pair of moly with a couple of platies in a 10 gallon tank.


Tetras are one of the best options for a platy tank, but you need to keep six tetras and a 20 gallon tank.


Snails will eat algae and food waste and can benefit a platy tank.

Final thoughts

If you want to keep platies for their whole life, provide two gallons of water for each fish. Five platies will be able to swim, feed and live comfortably in a 10 gallon tank. Plant some plants for better water quality and keep some hiding places so the platies can explore.