If you’ve been thinking about buying a fish tank, you’ve probably thought about how it will look, where you’ll put it, and the kind of fish you’d like to keep. But have you thought about what size fish tank will be best for your space?
Fish make ideal pets: they’re serene to watch, easy to care for, and available in an array of colours. They can brighten virtually any home (or workplace) and become the focal point of your chosen room. But choosing the right size fish tank is one of the biggest challenges new fishkeepers face when aquarium shopping.
If you’re a new fishkeeper, you can find everything you need to know about fish tank size here.
Know where you'll put your fish tank
At the simplest level, your fish tank must fit in the area you’re planning to keep your fish. Before you decide on this space, take a look at our blog post on how to find the best spot for your fish tank.
Once you’re happy with the location for your new fish tank, measure the area to know the maximum aquarium size you can go for. When you shop for your aquarium, you’ll find that fish tanks are labelled by their water capacity rather than their physical size. But click through to the fish tanks on our website and you’ll find measurements for each too.
When measuring for your aquarium, remember to make allowances for the fish tank stand or alternative surface that you’ll place your fish tank on. If you’re not using a fish tank stand, make sure the surface your fish tank will stand on is strong, flat, and robust enough to support it. Fish tanks are heavy when filled with water (each litre will weigh around one kilo). If you’re not sure whether your surface is strong enough to hold a fish tank, you can work out how much your aquarium will weigh using this fish tank weight calculator.
Also, keep in mind that a fish tank that overhangs its surface is more likely to crack and leak. In this case, not using a fish tank stand will invalidate your manufacturer’s warranty. Therefore, we recommend buying a fish tank stand for your aquarium. We sell standalone fish tank cabinets and fish tanks that come with cabinets designed specifically for these aquariums.
Know which breeds of fish you'll keep
Once you’ve worked out the maximum size fish tank you can keep, it’s time to think about the kinds of fish breeds you’d like. Remember that fish come in different sizes, and different fish need different size spaces.
- Some of the best fish for 10–20L tanks include chilli rasboras, male endlers, ricefish, common tetras, sparkling gourami, and neon tetras.
- Some of the best fish for 30–40L tanks include platy fish, mollies, small rasboras, gold/white cloud mountain minnows, guppies, dwarf/pygmy corydoras catfish, otocinclus catfish, and small danios.
- Some of the best fish for 50–60L tanks include goldfish, giant danios, swordtails, dwarf gourami, kuhli loach, brown pencil fish, and cherry barbs.
- Some of the best fish for 70–80L tanks include dwarf south American Cichlids (buy in a pair), bristlenose plecos, and rainbow fish.
- Some of the best fish for 90–120L tanks include rams, gourami, angel fish, apistogramma, and Siamese flying fox.
*Many of these fish are tropical, which require a heater to make the fish tank water warmer than coldwater fish tank temperatures. Find out how to set up a tropical fish tank here.
It’s essential to buy the right fish for the size of your fish tank. If your tank is too small for your fish, you could stunt their growth and shorten their lifespans. So, if in doubt, speak to one of the pet shop assistants when choosing your fish.
Know how many fish you'll keep
When you know which breeds of fish you might be interested in, you can find out how many of these fish you can keep in a tank of your given size. Speak to one of the pet shop assistants about how many of these fish should school together. This is especially important if you’ll be mixing breeds as some fish are happier to live together than others.
At the simplest level, the smaller the fish, the more you can keep in your tank.
Know that smaller fish tanks are harder to maintain
Contrary to common misconception, smaller fish tanks aren’t easier to maintain than larger fish tanks. It’s actually much harder to maintain good water parameters (like pH levels, ammonia levels, and temperature) in a small tank. So, small tanks need cleaning and water changes much more often than tanks.
Therefore, it can be best to opt for the biggest fish tank you can fit in your chosen space as long as your budget allows.
Calculating what size fish tank you need
You should now have all the info you need to work out what size fish tank you need.
Whatever size you need, we’re always on hand to help you find the right fish tank, and we stock aquariums in all sizes:
If you need any further advice on what size fish tank to go for, get in touch with our customer service team.
About Warehouse Aquatics
The Warehouse Aquatics mission is to offer the most choice at the best prices when it comes to your fishes’ wellbeing. We use the products on our website ourselves and are well-versed in all things fish, so we can give you all the advice you need. We’re not just here to sell aquatic supplies. We’re also here to guide you through your journey as a fish owner and enthusiast.
As a small team, we love to hear from our customers, so please do join the Warehouse Aquatics social media community. We’re always up for a chat, and we’d love to share your aquarium photos with our followers.