How to: Set up & maintain a freshwater aquarium

Setting up an aquarium can be an enjoyable and rewarding hobby for both adults and children. It’s been shown that watching fish in a healthy and well maintained aquarium can reduce your stress levels. But before purchasing an  aquarium, you should consider all the aspects raised on this page to ensure the underwater community which you choose to create is looked after properly, and that the fish remain healthy. As a general rule you should, within reason, buy an aquarium as big as possible. Larger aquariums contain more water and it is easier to maintain a healthy environment for your fish.

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See below for our top tips.


Before you buy your fish make sure:
• You’ve the correct equipment and position for the aquarium

• You’ve researched all the species you are interested in and
your final choices are all compatible to live together

• You’re familiar with how to transport and release your fish

• You’re aware of the daily, weekly and monthly maintenance
your aquarium will need

• You’re prepared to look after your fish properly for the
duration of their life


A generalised checklist for a freshwater aquarium should
include the following:
• Glass or acrylic aquarium
• Suitable stand (if appropriate)
• Gravel
• Filtration
• Lighting
• Secure lid
• Siphon cleaning device (recommended)
• Ornaments
• Plants
• Heater (tropical set-ups)
• Water conditioner/dechlorinator
• Thermometer
• Water testing kits
• Food

Positioning your tank

Once all of the equipment is ready, the tank should be
positioned carefully so it is:
• Out of direct sunlight and away from sources of heat.
• On a perfectly level surface or stand which can indefinitely
support the weight of the tank when it’s filled with water.

Adding Fish

Before adding any fish, research the species you are interested
in as not all fish will live peacefully together. Different species
may also prefer different water types.

Patience is a virtue; add fish slowly. Overstocking or stocking
too quickly may cause ‘new tank syndrome’ when the filter is
not capable of coping with the increased waste load. Ammonia
and nitrite can quickly build up to unhealthy levels and often
fish will not survive.

Healthy fish have clear bright eyes, undamaged fins, intact
scales, no ulcerations or bumps, appropriate swimming and
steady breathing. Do not purchase a seemingly healthy fish if
sickly fish are present in the tank with it. Fish diseases can be
easily carried without showing any symptoms. If in doubt ask
one of our Aquatics Team for advice.

Stocking Levels

It is not possible to say exactly how many fish your aquarium
can hold - the differences in size, species requirements, water
parameters and compatibility of fish available are vast. Ask our
Aquatics Team for advice.

Aim to create as natural a set-up as possible, for example
shoaling fish need to be kept in numbers. Remember that
decoration and plants take up space, however these are
recommended additions. Live plants help to remove nitrate and ornaments can provide less boisterous and reclusive fish
with a safe retreat.

The diet and feeding requirements vary between species. Some
feed at the surface; others will be found throughout the water,
while others will spend most time at the bottom of the tank. Be
sure to have suitable food to cater for all of your fishes’ needs.
Do not expect to fill your tanks with as many fish as the stores
do, they are able to do this due to expertise and advanced
filtration systems. Some species require bright lighting, others
fast water flow. Ask our colleagues for advice, it is often simple
to adapt your aquarium for species’ requirements. The closer
the aquarium mimics the natural environment, the healthier the
fish will be.

Never release your aquarium animals or plants into the wild

Never release an animal or plant bought for a home aquarium
into the wild. It is illegal and for most fish species this will lead
to an untimely and possibly lingering death because they are
not native to this country. Any animals or plants that do survive
might be harmful to the environment.