Which Size Tank Should I Buy?

Choosing an aquarium can seem the most logical first step when starting out in the hobby but working backwards (choosing the fish first) is actually the best option

A great first step is to walk around a fish store and decide which fish you most like the look of. Make a note of the species and look online for information about the fish. A great place to start is aquadiction.world
We really like this site for the in depth advice and information that they provide. The information of particular interest is maximum size, activity levels and minimum group size. This will give you a good idea of how large of a tank they will need. Another great place to get species profiles is YouTube. Be aware that the information that they provide is based on their opinion and experience so watch a few different videos to gain as much knowledge as possible. I'll leave a few links to some great channels at the end.

So now you won’t be making the mistake of buying a tank only to find that you can’t keep the fish that you had your heart set on. However, there are some other factors that you should consider as well.

1. How many fish?
One of the most commonly asked questions is “how many fish can I put in my tank?”. We won’t be going in to too much detail here because there’s no short answer and this subject deserves its own blog. However, it is a question that you should ask yourself before buying your first tank. Again, this requires research and you’ll find a wide variety of opinions online so it’s worth watching lots of videos and reading lots of articles.

2. Mixing species
The most common setups are community tanks. These are tanks with lots of different species of fish kept together. It’s a great way to experience the joy of keeping different species without have multiple tanks but it does make things more complicated. Most fish that are termed “community fish” are non-aggressive and will happily share their home with other species. However, even peaceful fish can get a bit boisterous if their needs aren’t met.
Once again, research comes in to play. Find out if your desired fish need their own territories. Some bottom dwelling fish need their own caves and will defend the space around them. These caves and territories take up space, so you’ll need to consider this when looking at tanks.

3. How often do you want to be performing tank maintenance? 
A larger tank may seem more work but the opposite is true. The larger volume of water in a big tank helps to dilute pollutants produced from fish waste and uneaten food. The levels of toxins in a small tank build up very quickly whereas a large tank can go much longer before needing maintenance.

4. Will you be using live plants? 
Live plants are natures filter. They consume some of the pollutants that build up in the water meaning that water changes can be performed less frequently. Of course, you’ll still need to test the water regularly and change water as required but a planted tank can enable you to stock slightly more fish than a non-planted tank.

    Another important factor to consider is whether your floor is capable of supporting the weight of a large tank. If you have wooden floorboards then first you should check to make sure that the floor isn’t bouncy which could indicate that there’s an issue with the joists. Providing the floor is sound then I personally don’t worry at all unless the tank is over 400 litres. If you’re in any doubt then you should contact a professional for further advice.

    To summarise:
    It’s always best to buy the largest tank possible. This gives you more options if you wish to add more fish in the future and reduces maintenance. You will also see more natural behaviour from the fish in a larger aquarium.
    Research is key to success. This point really is important to emphasize. The vast majority of problems that new fish keepers run into can be easily avoided by doing plenty of research. It’s worth mentioning that whilst most fish stores will give you great advice, it’s worth getting more information from others or by searching online.

    Hopefully this blog has helped you. If you have any questions or comments then please leave them below. You can also contact us for free advice.

    Our favourite YouTube Channels for species profiles:
    Prime Time Aquatics
    Aquadiction
    Aquarium Co-Op
    Steenfott Aquatics


    Leave a comment

    Please note, comments must be approved before they are published

    This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.