Best Tank Setup For Platy Fish

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Getting the size of the tank right makes a big difference to the health and happiness of your Platy fish. But it’s not just the size of the tank that’s important. The general tank setup makes a big difference too.  

So what size tank do Platy fish need?

And what’s the best tank setup for Platy fish?

When I first got my Platy both of these questions got me thinking. I wanted to make sure I was doing the right thing and taking care of them properly.

Afterall, I was new to the fishkeeping hobby. I’d ‘adopted’ my new little fish from my son’s community tank which was becoming overstocked because of the Platy’s natural urge to keep reproducing babies.

I fell in love with the tiny fry and set about making them a new home.

Read on to find out what’s needed to create a happy and healthy Platy aquarium.

Choosing A Tank For Your Platy Fish

It’s very tempting to choose a tank before deciding on how many fish that you want to live in it. After all there’s some attractive aquariums and aquarium kits out there.

It’s just so easy to go ‘Oooh that will look lovely full of fish!’ and forget to think about the needs of the fish that will live in the tank.

Making a decision on how many Platys you want to keep is the best place to start. Once you’ve made that decision you can then choose a tank that’s suitable for your Platys’ needs

Here’s a few pointers to help you to decide how many Platy to keep

Because Platys are happiest living in groups it’s a good idea to have at least 4 or 5 Platys in your aquarium. You can have a lot more Platys of course if you would like to. But 4-5 is a good place to start if you’re new to the fishkeeping hobby or you’re adding Platys to an existing aquarium.

If you’re going to keep both sexes of Platy fish in your tank you’ll need to get the male/female ratio right. This helps to prevent your females getting stressed out by the amorous attention of the males. So if you have 1 male to every 3-4 females you will have the balance about right.

Be warned though! Platys are prolific breeders which means that the population of your aquarium is going to increase at regular intervals. Not all of the baby Platys (fry) will survive but nonetheless you can end up with far more fish than you bargained for. 

So you’ll need to factor in room for your new arrivals when choosing the right size tank for your Platy fish.

You can just keep one gender of Platy if you don’t want them to breed. 

While it is possible for an all male Platy aquarium to be harmonious there is a chance that one or more of your males will try to gain dominance over the other males. So despite the Platys normally gentle temperament you can end up with some pretty aggressive fin nipping and infighting.

An all female tank is less likely to become a battleground. Although that’s not a certainty as some female Platys can be quite dominant. 

Basically it will come down to the personalities of your fish.

How Do I Calculate What Size Fish Tank I Will Need?

Because having enough room is an important factor in keeping your Platys fit and lively you do need to do a little maths. 

I’ve found that opinions vary on how to calculate how much space aquarium fish need. But there is a general guideline that you can use which simplifies things a little to start with.

• Allow 1 gallon per 1 inch/2.54 cm of fish

You do need to know how big an adult Platy is likely to be though. It’s no good judging tank size on the young Platy that you’re buying. 

You should calculate the size of the tank you’ll need for when your Platys are all grown up.

This kind of calculation is a great starting point but there are other things you have to take into account too. 

You’ll need to adjust the calculation if you’ve got all male or all female Platys as they do generally differ in size. 

One of my male Platy fish is almost the same size as my slightly smaller female. Which goes to show that sizes are only approximate and not a certainty.

So be generous in your calculations when it comes to minimum tank size.

And as a final note on tank size for Platy fish there is something that I need to point out. 

Because Platys like to live in groups, are a non-aggressive but tough little fish, it’s possible to keep quite a few together and still have happy healthy fish. 

If you have experience in the fishkeeping hobby you can have your aquarium a little fuller than is usually recommended for a beginner. You will be able to rely more on your own judgement and knowledge of Platy fish rather than the calculation of inches per fish and gallons of water.

Can I Add Platys To An Established Aquarium?

If you already have a community aquarium but would like to add more colour and movement the Platy fish is a great choice.

Your community tank needs to be a peaceful and non-aggressive one to allow your Platy fish to thrive. 

Platys are happy to live with other peaceful fish such as Guppies, Mollies and Swordtails and also with non-aggressive shrimp and snails. In fact there’s lots of possible tank mates for your Platys.

Again you need to take into account how much room there is in your tank. 

Calculate how many fish inches you already have in your aquarium. Allow a little extra space if some of your fish have chunky bodies rather than sleek figures.

You’ll then know how many gallons/litres you have spare for Platys.

Then use the calculation guide above to work out how many Platy fish you have space for.

If you’re experienced at keeping fish, then, as I mentioned above, you can use your own judgement and knowledge when adding Platys to your existing aquarium. Just remember to take into account the Platy fish’s ability to reproduce regularly.

Once you have decided how many Platy fish you will keep, and you have calculated the size of tank you will need, there are a few other important things to know before adding your Platys to the tank.

What Kind Of Water Do Platy Fish Need?

The Platy is a tough little fish that can survive quite happily in a wide range of water conditions. Although that doesn’t mean that you shouldn’t be trying your utmost to provide them with the best aquarium water quality that you can. 

And as you’ve chosen to keep Platys, doing your best for them is naturally something that you’ll want to do. 

But what water parameters do Platy fish like best?

I have to admit that when I first looked into this I found it all a bit technical. I was only a beginner at the time. And despite keeping Platys for a fair while now I still find it all a bit daunting when it comes to the ‘scientific’ details.

Below is the general guide to the best water parameters for Platy fish. 

I’ve tried to keep it simple and you will need to bear in mind that opinions in the fishkeeping world do vary a little.

Here goes:

• Water Hardness 10-28dGH
• PH 6.8-8.3
• Ammonia 0 ppm
• Nitrite 0 ppm
• Nitrate 40 ppm maximum

But what does all this mean?

Unless you’re familiar with the more scientific aspects of aquarium water quality you’re likely to be as baffled as I was. 

Here’s a simple explanation of what each aspect listed above means

• Water Hardness = how much calcium and magnesium are in your water supply
• PH = how acid or alkaline your water supply is
• Ammonia = byproduct of waste (poop. leftover food, plant debris)
• Nitrite = byproduct of waste (poop, leftover food, plant debris)
• Nitrate = byproduct of waste (poop, leftover food, plant debris)

As you can see the last 3 items on the list are produced by waste of different kinds. It’s a good reminder that regular tank maintenance is important to the health of your Platys.

It’s also worth bearing in mind that Platys prefer their water to be on the harder and slightly alkaline side where possible.

What’s The Best Way To Test Aquarium Water?

It’s a good idea to test your tank water once you’ve done your initial setup and before you put your Platys into the aquarium. Particularly if you have concerns, or are just not sure about, the quality of your water supply.

You can also do regular water quality checks as part of your usual tank maintenance, just to make sure all is well. It’s a good way to monitor whether or not you need to increase the regularity of water changes, or whether adjustments need to be made to the water quality.

Testing the water in your aquarium is also useful for identifying a problem if you see that your Platy fish are not looking too happy but aren’t showing signs of actual illness.

Sometimes, despite your best efforts, and your tank looking nice and clean, there can be a problem with a buildup of toxins in the water. Toxins lead to ill health, and even death in the aquarium. By checking the water quality and putting things right you can avoid a catastrophe.

Aquarium Water Test Kits

You can buy a range of aquarium water test kits that are simple to use. They can help you identify a water problem and, most importantly, help to keep your Platy fish happy and healthy.

Most of the aquarium water test kits I’ve seen come in the form of ‘dip test strips. The sort of thing you might associate with a doctor or nurse testing a urine sample. Or you might remember them from a school science lesson to test acid and alkali. 

I’m sure you get the picture.

They are handy to have around as you never know when a problem may crop up in your aquarium. Testing your water may be your first line of defense in solving a problem in your Platy tank.

Aquarium Water Treatment Products

It’s also important to use a water treatment that makes tap water safe for use in aquariums. Aquarium water treatments get rid of chlorine, chloramines and also neutralise heavy metals in your tap water. 

Even though having these in our tap water is considered safe for us it’s not good for your Platys.

You should always treat your aquarium water on tank setup. And also at every water change. Doing this will eliminate anything in your tap water that can be harmful to your fish.

The good news is that water treatment products are inexpensive, easy to add to the water, and widely available. Which is a bonus as the fishkeeping hobby involves regular tank maintenance. 

Just be sure to buy a good quality one that you’re confident will do the job.

Do Platys Need A Heater?

This is a really interesting question. Platys are a tropical fish so warmer waters are their natural habitat.

But does that apply to Platy fish that are aquarium bred?

My Platys parents were originally in a tropical aquarium. I say originally because by the time my son took them on from an elderly neighbour they hadn’t been heated for some time.

I know this might sound bad. But the neighbour who wanted to rehome the fish was left with the fish tank after her husband had died. The fish were his hobby and she knew very little about fishkeeping apart from that they needed feeding.

Despite this they had survived well with the minimum of losses

So Do You Need A Heated Aquarium To Keep Platys?

This is one of those ‘Yes And No’ answers. Because whether you need a heater or not will depend on a few things.

Yes If . . . . .

If the Platys you want to buy have been reared in a heated aquarium by your Pet Store, Dealer or Breeder then you should have a heater in your fish tank.

No If . . . . . 

If you choose Platys that have been reared in a temperate environment by the Pet Store, Dealer or Breeder you won’t need a heated aquarium. 

But . . . . . 

It is possible to acclimatise Platy fish from tropical to temperate and vice versa. However it’s a long process because an abrupt change in temperature is harmful, even deadly, to the fish. If you do want to change your aquarium from one to the other it’s best to get some professional advice from your supplier and follow that advice closely so that you don’t lose any of your Platy in the process.

Also . . . . . 

If you have a temperate tank in your home you will need to take your country’s natural climate into account along with how warm you keep your home all year round.

If the country you live in has an all year round milder climate, and your home generally stays at a  pleasantly warm temperature, your Platys are likely to be fine without a heater.

However, if your winter months are cold, or exceptionally cold for long periods, you will probably need a heater in your Platy tank. Even if you only need to use it during colder weather to keep the water temperature comfortable for your fish it’s worth investing in one.

Get yourself an aquarium thermometer too so that you can keep a check on the water temperature. That way you’ll know when it’s time to switch the heater on.

What Water Temperature Do Platy Fish Need?

Although you might not necessarily need a heater in your Platy tank it’s good to know what temperature your fish prefer.

Opinions do vary a bit about the optimum temperature for a Platy aquarium and the recommended range is fairly wide 

Here’s a general guide for you to use:

68 – 78 Degrees Fahrenheit (20 – 25 Celcius)

So if your tank stays between these markers your Platys will be comfortable. Even if the water temperature is a little higher or lower in general, Platys can tolerate the difference really well as long as the temperature change is gradual.

Do Platys Need A Filter?

A tank filter is an important piece of equipment in any freshwater aquarium no matter what fish you choose to keep.  

The job of the filter is to remove toxins from the water and to stop tank debris, such as leftover food and poop, from fouling the water quality. So you end up with cleaner and healthier water for your Platy fish to live in. 

Your tank will look more attractive too if the water is sparkling clean.

Because Platys poop a fair bit they benefit from having their water filtered 24 hours a day, along with the regular water changes and general tank maintenance that you do. 

So I would say yes, Platys do need a filter, just like any other freshwater aquarium fish do.

What Kind Of Aquarium Filter Do I Need?

There are different ways to filter your tank water and there’s a wide choice of aquarium filters available to suit your Platy’s needs.

Internal Filters

The most common type of tank filter, and probably the most popular, is the internal filter. This kind of filter sits in the water inside your aquarium and continuously filters and cleans the water removing toxins and debris.

Internal filters come in different shapes, sizes and capacities so you’ll need to choose one that’s right for the size of your tank. So apart from deciding on the style of filter you want you need to buy one that’s suitable for how many gallons/litres of water your tank holds. 

You’ll also need to take into account how many fish you have and how messy they are. More fish = more mess = the need for a higher capacity-per-hour filter to keep the water healthy and clear.

External Filters

Unless you have multiple tanks, or your aquarium is seriously large, you’re unlikely to need an external filter system for your tank setup. But then again, you may just prefer to filter the water this way. 

The choice is yours.

Just as it sounds, an external filter sits outside of the tank(s). It pumps the water out into a filtering unit, cleans it, then pumps it back into the tank on a regular cycle. How many gallons/litres it cleans an hour will depend on the filter’s capacity. 

You will need to buy the external filter best suited to the volume of water in your aquarium(s). And just like an internal filter you need to take into account how many fish you have and how much mess they produce.

Do Platys Need An Air Pump?

Although water naturally contains oxygen it’s depleted pretty quickly in a tank environment. And as Platys need oxygen to survive you will need a reliable way of keeping the oxygen levels up in your aquarium.

So What’s The Best Way To Keep Aquarium Water Oxygenated?

Here’s some simple oxygenation solutions

Dual Purpose Water Filters

A lot of water filters have a dual purpose. They oxygenate the water at the same time as cleaning it. The way they put oxygen back into the water will depend on the type of filter you buy.

Some water filters emit lots of bubbles that force oxygen into the water from an external air tube. The bubbles then rise up to break the water surface letting yet more oxygen in

Others filter the water through in a waterfall effect. The pouring water creates small bubbles that rise and break the surface of the water. The cascading water continuously breaks the water’s surface letting more oxygen in too.

But not all filters do both jobs. 

If that’s the case with your chosen water filter then you will need to get oxygen into the water another way. 

External air pumps will help you to do this.

External Air Pumps

Getting yourself an external air pump is another way to keep up the oxygen level in your aquarium. You can attach the air tube to a tank ornament that’s designed to let the air out in a plume of bubbles. 

There’s lots of fun decorative tank ornaments for sale. A deep sea diver, or a treasure chest, that emit bubbles are just two popular examples. But you’ll find loads more ideas that will compliment the look of your aquarium’s theme.  

If you want to keep it simple, or a little more discreet rather than ornamental, you can get oxygen into the tank through an air stone. 

Attaching an air stone to your external air pump tube will produce lots of bubbles that provide oxygen. The bubbles also break the water surface to let in more oxygen for your Platys.

It’s worth remembering that while air pumps provide oxygen they don’t clean the water. So you will still need a water filter of some sort to keep your aquarium clean.

Some General Points On Platy Oxygenation

If you have a large aquarium, or your tank is a well stocked and established community tank, it’s a good idea to have an extra air supply even if you have a dual purpose water filter. After all, more fish means the need for more oxygen. 

Plus, a plume of bubbles makes an attractive feature in your aquarium.

However, Platys tend to prefer a gentle water current. So making sure that your aeration system isn’t churning up the water too much is a good idea. Because, while Platys can enjoy playing in the bubbles, they don’t want to be constantly blown over sideways as they try to swim around the tank.

Do Platy Fish Need Plants?

The simple answer to this is yes. Platys prefer, and benefit from, having a planted aquarium. Because even though Platys are lively little fish that spend a lot of time darting around the tank, they love having places to hide for a while.

A pregnant female Platy will need a quiet, secluded spot, for when she’s ready to give birth to her fry. A space away from the main and lively part of the tank will be perfect for this. Plants are a simple way to provide this quiet space for your Platy mum-to-be. 

And Platy fry themselves need small hiding places to avoid being eaten by the adult Platys if they’re going to have any chance of survival. Being eaten at birth is a real danger because Platy parents have no protective instinct for their offspring.

What Kind Of Plants Are Best For Platy fish?

Live Plants For Platys 

Live plants not only provide hiding places, and spaces for Platy fish to rest in, they also have other benefits for the tank environment.

Living plants play a part in releasing oxygen into the water. They can also help with filtering out toxins that naturally build up in an aquarium.

And in addition to this, live plants can help to create a more natural environment for your Platy.

There are loads of living plants that are suitable for aquarium use and you’ll probably find a wide range at your Pet Store or Aquatic Supplier. You can order them online too.

But which live plants are good for a Platy fish aquarium?

Here’s A Few Plants Often Recommended For Use In A Platy Tank

• Java Moss
• Java Ferns
• Hornwort
• Duckweed 

These are all considered easy maintenance aquarium plants. 

But, if you go for the Duckweed it’s best to choose a larger leaf variety. Or you’ll end up with a tank surface that looks like it’s covered in slime.

There are loads more easy to care for aquarium plants that you can use in your Platy tank. 

You might want to consider some of the following ones:

• Cryptocoryne Wendt (Red) and Lutea
• Marimo Moss ball
• Anubias (Various)
• Jungle Val

I know the ‘proper’ names for these plants can seem a little overwhelming (or is that just me?). But at least if you know what you’re looking for you’ve got a head start. And a good stockist can give you advice and also help you to choose the ones that are right for you.

Even easy to care for live plants may need a little attention now and again. So whether it’s the use of fertiliser, a regular trim, or their lighting requirements, it’s best to know what the plants will need from you before you head to the checkout.

Artificial Plants For Platys

Not everyone wants a live planted aquarium. So it’s handy to know that Platys do well in a tank that has artificial plants instead.

The plants will still provide much needed shelter for fry, and places to hide or rest in for the adult Platys. 

There’s a huge range of artificial plants that you can choose for your tank. Whether you want a more natural look, or a bright and colourful theme, there’s no shortage in artificial aquarium plants for sale. 

Artificial plants are a great way of enhancing the theme of your tank. Particularly if you’re going for a specific look or colour combination. 

A word of caution though.

Avoid artificial plants that have spiky or rough edges. By doing that you will reduce the chance of injury to your Platy fish as they dart around the tank and through the plants. A flesh wound can lead to infection or worse. So check the texture of the plant before you buy it. 

That doesn’t mean that you can’t have ‘spiky looking’ artificial plants in your aquarium. It just means that you need to do a risk assessment on them first. 

Better safe than sorry.

Live/Artificial Plant Combination For Platy

There’s nothing to stop you from combining both live and artificial plants in your Platy aquarium. You’ll get the water quality benefits of the live plants and the additional aesthetic look from the artificial ones. 

Even if your tank is predominantly live planted you can enhance the look by adding some artificial aquarium plants too. 

What combination of live and artificial plants you use is completely up to you.

Do Platy Fish Need Tank Ornaments?

If you’ve provided plenty of plants for your Platy you probably don’t strictly need to have tank ornaments. But ornaments can provide extra nooks and crannies for both young and adult platy to take a break in or to hide behind. 

You can make it all look natural by using rocks and pebbles, or pieces of wood for example. Or you can go all out on a theme. No matter how outlandish the theme you choose your Platys won’t mind as long as you give them the environment they need.

Do Platys Need A Substrate?

At the beginning I didn’t know what substrate meant (honestly). When I realised it just meant the gravel at the bottom of my fish tank I felt a little silly. It was simple. But I’d never heard it called that before so I thought I’d been missing something

Fortunately I’d provided my young Platy with a tank equipped with a substrate in the form of multicoloured gravel. 

A substrate doesn’t have to be gravel although it’s probably the most popular way to do it. You can also use a sand/gravel mix, pebbles or small rocks. I’ve even seen tanks that have a slate type of substrate which looks really effective. In fact there’s lots of options for the kind of substrate you can use in your freshwater aquarium.

But do Platys actually need a substrate in their tank?

The substrate not only makes the tank look good it also plays several important roles.

One of the things it does is to help filter tank debris such as poop and leftover food. And keeps it at the bottom of the tank making it easier to remove.

You do have to do regular gravel cleaning to remove poop and leftover food so that it doesn’t rot and pollute the water to a dangerous level. But the bacteria that’s always left behind is beneficial for your Platys. 

Your substrate is the ideal place for beneficial bacteria to grow. This good bacteria helps to keep the water quality safe for your fish while, at the same time, it helps to break down your Platys natural waste.

A substrate is also important if you want to keep live plants in your aquarium. It gives them something to root themselves into. The plants also use the poop as fertiliser, breaking it down for their own use. With the knock on effect of helping to keep the tank clean.

Do Platys Need A Light?

While the Platy fish is not considered a light sensitive fish it does benefit from having a lighted aquarium. That doesn’t mean the light has to be bright. Soft lighting may be better but I can’t find a definitive answer on how bright the light should be.

My Platy tank has soft lighting because I didn’t want a really bright light in the tank. That was just my personal choice. My Platys seem content and healthy so I guess they are happy with it too.

There are some obvious reasons for having an aquarium light. 

The fish can see better. 

You can see the fish better. 

An unlit aquarium tends to look like a dull black box lacking activity and interest. One of the most important pleasures of the fishkeeping hobby is being able to enjoy seeing your fish in their full glory. 

Which is hard to do in the dark.

But there are other benefits to having your aquarium lit.

Benefits Of Lighting In A Platy Aquarium

• Better visibility for your Platy to navigate the tank, find their food and also for breeding
• Easier for you to see your Platy to check on their health and for you to enjoy seeing these lively, colourful little fish at their best
• Your tank looks more attractive with plants and ornaments being lit
• Live plants need light to grow so that they can benefit your tank environment

How bright you have your tank lighting will depend on a few things. Your personal preference is one. 

But there are other considerations.

If your Platy fish are in a community tank you will need to take into account recommended light levels for their tank mates. Platys are easy to please. But your other aquarium inhabitants might need something a little more specific when it comes to light levels. So you’ll need to find a happy medium.

And if you have live plants in your tank you’ll need to check what kind of light levels are best for them to thrive too.

It doesn’t have to be complicated. Just do a bit of research into the fish and plants you have to check on prefered levels of light. Or get some advice from your local Pet Store or Aquatic Supplier. 

You’ll find plenty of aquarium lighting solutions to suit your needs and taste. And also to suit the size and style of your fish tank.

Light and Dark

Don’t forget that just like us fish need periods of light and dark. The cycle of day and night is natural for all creatures. 

So it’s not a good idea to leave your tank lighting on 24 hours a day. 

Between 8-12 hours is generally considered enough artificial light in an aquarium. And if you can keep the periods of light and dark regular it’s even better.

You can set your tank light up on a timer switch. Or buy one with a built in timer. Either way, you won’t have to worry about remembering to turn it on and off at set times.

Platys are easy to please. This makes them an ideal beginners fish as well as a colourful and lively addition to an established community aquarium. But they do need at least the basic things I’ve mentioned above in their tank to keep them happy and healthy.