40 Litre Fish Tanks

40 Litre Fish Tank

If you are looking for an aquarium to introduce your kids to then a 40 litre fish tank is the perfect size of tropical starter aquarium for children. They are large enough to hold a decent number and variety of fish, along with all the decorations and equipment that go with them.

Children are often easily bored and giving them a large enough tank that they will be able to sculpt their own miniature world will be a great step in helping to hold their interest and increasing their enjoyment.

At the same time, a 40 litre aquarium is not so big that it will require an overabundance of support equipment or involve a great deal of work to keep up with its required regular cleaning and maintenance. Nothing will destroy a youngster’s interest faster than making it too big of a chore to take care of.

Setting Up a 40 Litre Fish Tank

Premium Interpet Insight 40L Full Kit

Fluval Edge Aquarium 46L

Nano Starter Aquarium 40L

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What You Will Need

Setting up a 40 litre fish tank, for tropical fish, is relatively easy and quick. Many tanks now come in a complete kit form containing everything that you need to get started. This means all you are required to do is put all the perfectly matched pieces gather. You don’t have to worry about forgetting anything or wondering if the filter system is large enough. These kits are designed by aquarium professionals to be about as fool proof and worry free as they can be.

However, if you buy a tank alone, you will also need to purchase suitable support equipment to go along with it. You will need a filtration system with a high enough flow rate and the sufficient capacity to keep the water in your tank clean and free of waste.

You are also going to need appropriate lighting. As a general rule, you can figure the proper power of your lights at one to two watts of light, per litre of water in your tank as being more than sufficient.

To heat the water to the correct temperature for tropical fish, 24 – 27 degrees centigrade (75-80 degrees Fahrenheit), you will also need a suitable heater. There are differing opinions on what is the best way to set up the heaters in your tank, with some people believing it is better to use two smaller heaters rather than one larger one. And, some believing it is better to place heaters closer to where your filter return feeds into the tank for better circulation, while others say this creates stress on the heater’s glass casing. There are pros and cons to all of these arguments and what will work best for your aquarium is largely a matter of taste.

Besides the above you are going to need:

    • Substrate (Gravel)- This comes in a huge variety of colours and textures so you can create just about any type of effect that suits your or your child’s fancy.
      Plants- Live plants are better for the tank because the help clean the water and maintain oxygen levels but fake ones can be more colourful and vibrant for children to view and are more easily swapped out as your child develops the tank into their ideal vision.
      Ornaments- There is no end to the variety of ornaments and figurines that you can find for your child’s aquarium. There is now a trend for theming your tank with lots of different options available. Themes like football teams, TV characters, unicorns, and aliens are very popular right now, but it is hard to go wrong with the timeless classics like castles, scuba divers and treasure chests.

Aquarium Setup Procedures





Thoroughly wash everything that is going into your tank including the gravel. DO NOT USE SOAP OR DETERGENT. These are highly toxic to fish, just rinse with water until clean. A large strainer or colander is a great help here, but not a necessity.

    1. Put your gravel into your tank.
    2. Place a saucer in the bottom of your tank, this helps keep the gravel from being flushed around as you add water.
    3. Fill your tank about one-third full of water by pouring water onto the saucer.
    4. Hook up your airlines and other equipment then arrange the plants and figurines in the bottom of your tank.
    5. Finish filling the tank and let sit for three days before adding fish. This time is needed for the water gas off its chlorine content.

Starter Fish for Your Child’s Starter Tank

There is a plethora of fish available for your child’s new tank, but the 40 litre fish tank will only hold around 13, 3cm adult length fish and some fish prefer to be in small groups, others alone or in large groups. So, remember to take this into account when choosing.

Some possibilities include:

    • Cichlids
    • Bettas
    • Barbs
    • Cory Cats
    • Plecos
    • Guppies
    • Platys
    • Tetras
    • Goldfish
    • Darios

All of these species are fairly rugged and will be easy for your child to take care of.